Database Develop

Calls drop

Guys,
When I got my P3600 some weeks ago I didn't experience any problems with problems with calls dropping. But ever since I've upgraded to WM6 I am experiencing this problem... the calls drop at random, sometimes I can talk for hours without any disconnect, and sometimes the call drops and I cannot even call the person back... And even after downgrading to the shipped rom, I still have this problem... That made me wonder if maybe I have had problem when I got the device but at that point I was just lucky not to have calls dropping.
Yesterday was the last time a call dropped on me. I couldn't call the person back, the phone didn't establish a new connection. When I finally got the person back on the phone (2 minutes later) he/she said that the whole time she thought I was driving through a tunnel and that I would reconnect because... I stayed connected at the other phone... After 2 minutes, she said, the connection was finally broken and that's when I was able to call again.
So sounds to me that windows mobile disconnects me and that the operators network still keeps my number connected.
Well, needless to say, I want to fix this issue. I have a 3G Vodafone NL subscription but I read that 3G could be the cause of my issue. so I've just disabled 3G. Now I'm just running on GPRS... Which isn't how I want it to stay. Any ideas, same experience/ pointers how to solve this?
Thnx. Arend

Reply from HTC
This is the reply I got from HTC:
Try to remove it off 3G go to settings / phone / band - then select GSM from the top drop down menu.
Should now reset.
If it comes up with an error, turn on flight mode then do the above again.
Click to expand...
Click to collapse
So based on this reply it seems that 3G might be causing my issue.
I replied to HTC:
I have followed your instructions but now I can only use gprs... but I have a 3G subscription with my provider. So even if this workaround works, it's not to my satisfaction.
Pls advice.
Click to expand...
Click to collapse
I'll post their reply.
Further, if someone has more info on the subject please let me know.

Same problem here...
No issues before upgrading to WM6. Sometimes the call drops out after a few minutes, sometimes a few seconds, and sometimes already after a few rings. The other day I had to make a call 5 or 6 times to finish the conversation - very annoying...
I'm running the first official Australian WM6 release for Dopod/HTC, i.e. the one that got pulled off the web for a while. Possibly going to the newer release of the ROM update solves the problem? Even though I think both versions run on the same radio ROM.

I've used the same rom as you to upgrade to WM6. But in my case, even when downgrading to the shipped rom, I still had calls dropping. And like you, sometimes after minutes, seconds etc.
Still having no drops since I have turned 3G off. But I just wanted to look something up on the internet... took minutes to get the info on my screen with GRPS, so it's not much like a solution.

This is the reply of HTC:
Dear sir,
Regarding your situation with the device , I would suggest you, to? resolve your issue with the network coverage ,to practice a hard reset on your mobile with the following step:
START -> Setting->System->CLEAR STORAGE and follow the procedure, if you have already done this manipulation , I would direct you? to this service and check the right number on this area with your network ush the green button to call->then go to menu-> option ->Services->select the on the following list ->Voice mail etc-> and then get setting -> and check that the number is right with your network provider.
Click to expand...
Click to collapse
Needless to say, but I'll say it anyway, I have performed hard resets... indeed, multiple
The second action they adviced, sounded a bit strange to me. But when I retrieved the settings I saw that there was no number filled in for voicemail. So I've entered 1233 (Vodafone NL voicemailnumber).
So maybe the last action has nothing to do with my issue, but who knows.
So now I am running again on 3G. I'll keep y'all posted.

Just checked it on my device and there is already an entry under voice mail. So I severly doubt that it has anything to do with the voice mail settings, too.

No, I guess you are right.
Further, since I am running 3G my signal I noticed my signal is weaker then running GPRS-only. My calls have not dropped since but I do get complaints that people sometimes cannot hear what I say because my line goes dead, and a moment later it's back again.
I've got another reply from HTC:
---
If a hard reset didn't solve the problem and the problem only occurs when switching to 3G, than this can be caused by the following;
1. Problem with the device.
2. Problem with the network, ???
I would suggest to test your SIM in another HTC device with 3G and see what happens. If it happens again than it is a? problem with the network. If it works with that 3G device than it could be a faulty device. The experience is that it is related to the 3G network himself. If it is a network issue, than you can ask them to deactivate the 3G/HSDPA.
We can't find this out for you in the UK, you need to see if you could determine the problem yourself.
---
Thus the support of HTC.
So now I have written an email to vodafone. I'll keep you posted.

Same problem !
Try to flash your device with ROM_Radio 1.41.00.11,
Friendly

Barichon said:
Same problem !
Try to flash your device with ROM_Radio 1.41.00.11,
Friendly
Click to expand...
Click to collapse
Ok... but I'm somewhat confused... are you experiencing the same problem with 1.41.00.11? Or did you solve the problem by flashing to 1.41.00.11?

2----> solve by reflashing with 1.41.00.11

Ok, I've upgraded to 1.41.00.11.
So far, I've experienced no calls dropping on me.
Nevertheless, I've also made a phonecall to Vodafone explaining the issue. They acknowlegde the issue... SAY WHAT?!! Yes... they acknowledge the issue and recommend turning the device to GRPS only. WHAT?!!.. Chill, they can at least try that, who knows, maybe I would have said yes.
So, I explained GPRS only is not an option since it is a tiny bit slower then what I am paying for.
They've put the call through to their 2nd line and keep me informed. So as soon as I hear something I will get back to you.
ps. What I found very great is that they did not cut it off with "Ow, you are using the HTC P3600... I'm sorry, we do not support that device." Vodafone NL, keep up this great level of support!

Ok, so far I've heard nothing from Vodafone. And so far I have had one call that dropped. So although that is a huge improvement, it still sucks.
So... now what? The way I see it:
1. I want to have fast internet on my PDA (3G), so only GPRS is not an option
2. There are problems with the 3G network which make calls drop every now and then
3. Vodafone isn't going to fix this in a short period of time.
So the question is: what is more import to me: 3G or a reliable phone connections?
The answer is: reliable phone connection.
So I will switch my network to GSM instead of auto and when
I really need fast internet I will switch to 3G.
Case closed... well, not really... but still, case closed.

Hi
I think is not the operator problem and could be the phone problem, I am using the D810 in Singapore with Starhub and have the same problem with drop calls once I use 3G network. If I switch to GSM only than is perfect no drop calls and calls quality improve also.
So sad having a 3.5G phone and can't use 3.5G service

Could be, but HTC and Vodafone confirmed me that it has to do with the 3G network. And I do not want to know the technical details about all that so I'll leave it at that.

Call Ended 00:00

So I fanally got my Kaiser yesterday And It kicks @$$ XD
I live in Mexico, So it is an unlocked unit, and it recognized my local cel network as soon as I turned it on with the local carrier's sim (telcel).
One problem though: I can receive calls, but not make them... after dialing, I get the call dropped about 5 seconds later without tone that says "Call Ended" with time 00:00.
Anyway to fix this =(
I've tried the search and nothing popped out. Thanks! =)
- Jim

Sure
Welcome to AT&T.
I left verizon (due to their crippled hardware). I get virtually no signal in various parts of L.A. including my home. You place a call, their signal goes to zero, your call ends.
At least that's my 0:00 story.

I would like to reply to this...because I've been having this problem with AT&T consistently since I've come back to school (I go to school at Texas A&M in College Station)
I guess I could copy and paste a lot of stuff about it, because I've done a lot of posting about it on AT&T's forums...but I'm too lazy so I'll just put the link.
http://forums.wireless.att.com/cng/board/message?board.id=cingular&thread.id=76225&jump=true
My problem, however, is that when I have this condition, I cannot make OR receive calls (received calls go to voicemail, and although I see that I have a missed call or a voicemail message...I can't call the voicemail or I get Call Ended 00:00)
What I found was that whenever I'd call, the icon in the upper right hand corner (the one with the signal bars) would change from having bars and the phone icon to having bars and the 3g icon...it looks as if the phone TRIED to start dialing as a phone call, but changed to data, which knocked out the call.
If I connected to the internet, then I would get the H sign (so I know that 3g works). If I try to call with the H symbol, then the call connects every time.
If I use bandswitch, then I can eliminate the problem by FORCING the phone to go into 3g (UMTS) mode OR by FORCING the phone to go into Edge (GPRS) mode...the problem only exists when the phone is in auto mode (on bandswitch) or if bandswitch isn't installed. My problem is that bandswitch isn't a free program...so I only have a few more days of the trial before it expires.
I hope my topic on AT&T's forums has some helpful information

Subversive Asset 2.0 said:
I would like to reply to this...because I've been having this problem with AT&T consistently since I've come back to school (I go to school at Texas A&M in College Station)
I guess I could copy and paste a lot of stuff about it, because I've done a lot of posting about it on AT&T's forums...but I'm too lazy so I'll just put the link.
http://forums.wireless.att.com/cng/board/message?board.id=cingular&thread.id=76225&jump=true
My problem, however, is that when I have this condition, I cannot make OR receive calls (received calls go to voicemail, and although I see that I have a missed call or a voicemail message...I can't call the voicemail or I get Call Ended 00:00)
What I found was that whenever I'd call, the icon in the upper right hand corner (the one with the signal bars) would change from having bars and the phone icon to having bars and the 3g icon...it looks as if the phone TRIED to start dialing as a phone call, but changed to data, which knocked out the call.
If I connected to the internet, then I would get the H sign (so I know that 3g works). If I try to call with the H symbol, then the call connects every time.
If I use bandswitch, then I can eliminate the problem by FORCING the phone to go into 3g (UMTS) mode OR by FORCING the phone to go into Edge (GPRS) mode...the problem only exists when the phone is in auto mode (on bandswitch) or if bandswitch isn't installed. My problem is that bandswitch isn't a free program...so I only have a few more days of the trial before it expires.
I hope my topic on AT&T's forums has some helpful information
Click to expand...
Click to collapse
It sounds like the information on your SIM card could use an update.
Call AT&T and ask them to send an OTA to your SIM. If you don't have a current IRDB, your phone may not be picking up the correct tower or signal in your area.

I am not actually using it with AT&T... I use it with Telcel, a Mexican Cell Phone Network Service Provider, because it is where I live =).
Anyway, got it to work after a while. I went to Settings (Personal tab) > Phone > Services
I updated the data there; I also "re-found" my network in the network tab, but I'm pretty sure the first procedure got it going.
Tanks for your time.

When my phone was working, I tried to call AT&T locally, but they didn't know what was going on and didn't find anything wrong with the "network"

Subversive Asset 2.0 said:
What I found was that whenever I'd call, the icon in the upper right hand corner (the one with the signal bars) would change from having bars and the phone icon to having bars and the 3g icon...it looks as if the phone TRIED to start dialing as a phone call, but changed to data, which knocked out the call.
If I connected to the internet, then I would get the H sign (so I know that 3g works). If I try to call with the H symbol, then the call connects every time.
If I use bandswitch, then I can eliminate the problem by FORCING the phone to go into 3g (UMTS) mode OR by FORCING the phone to go into Edge (GPRS) mode...the problem only exists when the phone is in auto mode (on bandswitch) or if bandswitch isn't installed. My problem is that bandswitch isn't a free program...so I only have a few more days of the trial before it expires.
Click to expand...
Click to collapse
Under phone settings, there is a tab titled "band" (assuming you have it set to be shown, i think kaiser tweak/ reg editing can expose it) that you can switch between gsm and wcdma (G/E or 3g/H). I had that same problem when i first got my phone. i changed out sim cards a time or 2 and finally got everything working when i manually set the radio to one or the other. I've updated the radio a few times since then, but i still keep the switching manual, in an attempt to conserve battery power (I only need 3g/H when i'm online).

The problem with that is that AT&T branded Tilts never have this tab "band" and kaiser tweak doesn't expose it (I don't know what specific registry edit would expose it)...so I can't just switch between gsm, umts, etc.,
** Of course, I didn't check for an updated version of kaisertweak. One of the topics says it hasn't been updated in a while even though it has?
Yes, even WITH the latest version of kaisertweak and the latest version of the XML, turning on band (and then softreseted to make the options stick) does not make a "band" tab

Subversive Asset 2.0 said:
The problem with that is that AT&T branded Tilts never have this tab "band" and kaiser tweak doesn't expose it (I don't know what specific registry edit would expose it)...so I can't just switch between gsm, umts, etc.,
** Of course, I didn't check for an updated version of kaisertweak. One of the topics says it hasn't been updated in a while even though it has?
Yes, even WITH the latest version of kaisertweak and the latest version of the XML, turning on band (and then softreseted to make the options stick) does not make a "band" tab
Click to expand...
Click to collapse
curious, did you run the decert cab to allow unsigned code to run on your phone? could that be stopping changes from occuring?
heh, time to jump into the 'VOID' then? hardspl it and join the ranks of those who haven't bricked their phones yet! I guess i was lucky to have the band tab on the htc version.

I'm not sure how I would even know if I've run the decert cab or not?
Even though I guess this is the namesake of the site, I wouldn't want to change my ROM even though the AT&T ROM is doubtlessly inefficient as (insert inefficient thing here). To me, unless I know why the problem is happening, then attempting any solution seems counterintuitive (like giving the man the fish instead of teaching him).
So AT&T suggested just randomly sending a new SIM card (yet I know from other people's experiences that that doesn't necessarily end the problem) and AT&T has suggested to others that they get a new device (which has also not necessarily ended the problem.) These are just as shallow solutions until I know why the problem exists in the first place.

Jimmyy said:
So I fanally got my Kaiser yesterday And It kicks @$$ XD
I live in Mexico, So it is an unlocked unit, and it recognized my local cel network as soon as I turned it on with the local carrier's sim (telcel).
One problem though: I can receive calls, but not make them... after dialing, I get the call dropped about 5 seconds later without tone that says "Call Ended" with time 00:00.
Anyway to fix this =(
I've tried the search and nothing popped out. Thanks! =)
- Jim
Click to expand...
Click to collapse
Hey Jim,
I wonder how no one has pointed it out till now, but MAYBE it could be a problem with the Radio rom in ur phone.
Have u tried upgrading to a different RADIO? do u know which version it is?
The following radios have been doing great with ppl around here...
1.27.12.17
1.27.12.32
You can download them from here:
http://forum.xda-developers.com/showthread.php?t=349375
Try flashing one of the above mentioned and see if that solves ur problem!
hope this helps!

I guess you were addressing Jim, but I think I simply need to know if 1.27.12.11 for Radio is a known faulty radio (because that's the radio *I* have...so if other people know it to be faulty, then that's great for research)...and why? If so, then that would be the reason why it doesn't work (which is what I'm looking for) and then I'd be willing to switch easily.
But not before then.

Checking the radios topic, it seems as if no one reports a problem with 1.27.12.11
so...I don't know if switching is going to fix anything

I'm putting my problem on hold...it seems like it can transition better now and call out or receive calls better.

I've had the same problem with Telcel until I upgraded my SIM card to a 4.0.
The replacement costs $110 pesos (about $10 USD) and it's a quick and painless procedure!
Note: I still get the occasional call drop, but it improved things dramatically.
Try it out!
Cheers from Tijuana!
Rayan

my friend, I have the same radio 1.27.12.11
and the same problem.
I just found this topic searching why my phone do not work at 80% of the time, the mobile provider here in argentina recently told me "your phone have a problem" so I'm in crisis.
Let'see what happen updating the rom / radio / etc !!!

Unable to make a call in GSM network - works in 3G

My TyTN II is no more than one month old. Radio and ROM are all stock and I never tried any custom ROMs nor did I install hardSPL on it. The problem is all of a sudden I can't make any calls. If I dial a number it just says Call Ended following with couple of silent beeps. If someone call me they got to my voicemail. The strange thing is that after couple of retries, it works, I can make a call but then after another try, it stops working again.
In all that time, sending and receiving SMS works normally.
And now the very strange part of the problem. If I switch to 3G mode, everything is ok. No problems at all. If I switich back to GSM only mode, the problem is back.
I've contacted HTC in my country (I'm somewhere in Europe ) and all they can say is, hard reset your phone and if that does not work, send it for repair.
I consider that a valid response and I'm about to do just that but before I go and erase all of my applications and settings from my phone (which will take me ages to get them back) I was wondering if someone has previous experiance with this sort of a problem and if it can be fixed without hard reseting the phone.

I have the same issue but when I turn G3 mode ON. I can not make call with auto G3 mode on (I have to try a lot of times to make a simple call). If I use only GSM its works ok.

Zol
I have the same problem, i cannot make a call on 3g network only on GSM. I took the phone to the service and they said i had to change the motherboard it costs ~335 EUR. F*ck
Can anybody tell me an alternative solution?

"Call ended" right after dialing

First of all, I want to say that I found people with the same issue using Android everywhere and with a lot of different phones, so it's probably an Android bug rather then Moto X itself, but I wanted to leave my report.
I came from an S3, which suffered from the same problem when using Cyanogenmod. When using official Samsung ROM everything worked as it should. Now, I'm getting the same issue on my brand new Moto X.
When I try to call someone, sometimes it just doesn't call, after I press the dial button, it just hangs (without ringing) and finished the call with a "Cal ended" message. It happens randomly, and sometimes I can't call anybody for like 2/3 hours.
The simcard has been changed from the S3 (micro) to the Moto X (nano), so it's probably not it. Also, with the Samsung ROM it didn't happen.
I can still receive calls and messages, and the signal strength is fine most of the time. I just can't call.
Today I faced this problem and then I tried calling from my girlfriend smartphone (samsung ace IIx) at the same time, which is from the same carrier, calling to the same number, and it just worked fine. Mine still didn't work though.
Here is a thread on people on xda facing the same problem, but with a different phone: http://forum.xda-developers.com/showthread.php?t=2351227
Don't know what to do.

i've had the call not go through as you've described, but have never had a phone not let me place "any call" afterwards. i always chalked it up to poor performance (limited RAM, too many processes, etc). My DROID3 would do it and often times when it finally did make a call, there was zero sound and I would have to reboot the phone.

640k said:
i've had the call not go through as you've described, but have never had a phone not let me place "any call" afterwards. i always chalked it up to poor performance (limited RAM, too many processes, etc). My DROID3 would do it and often times when it finally did make a call, there was zero sound and I would have to reboot the phone.
Click to expand...
Click to collapse
Hmm, it doesn't seems like poor performance. I ended up every task and it still happened.
However, I noticed that when I check the "2G ONLY" option it comes back to work. Maybe it's something with the HSPA/HSPA+ connection.

it could be completely carrier dependent then. my experience has been with vzw.

Moto X "Call Ended"
I have experienced this same problem in Houston on the T-Mobile network after switching over to Android. My T-Mobile rep told me they have had towers vandalized for copper which has impacted service for them, I believe he said it was about 15 towers and 10K a pop to get things corrected. What gets me is I was on a Bold 9900 and while I had signal problems in the affected areas of town I didn't not experience the "call ended" issue. I can also call other T-Mobile phones from those same areas but not land lines so to me this seems like a possible network routing issue which I have seen before between specific carriers.
If the problem does continue I may have to switch carriers. T-Mobiles service was previously outstanding in Houston but recently had not been great after the 4G LTE upgrades. I support multiple hospitals and need service to work correctly and will work with the T-Mobile Engineers to see if I can make headway on that front. I noticed another MotoX user reporting he only had the issue when flying in to Houston for work and that everything worked for him outside of Houston. His solution was to operate in 2G mode which for me is really not an option. I have to handle a lot of tasks over the network while on calls.
Anyways I would appreciate it if others could post if they are experiencing these issues and give as many details as possible so we can try to isolate the root cause of this problem and if found to be a carrier issue we can escalate with them. Thanks
dicarli said:
First of all, I want to say that I found people with the same issue using Android everywhere and with a lot of different phones, so it's probably an Android bug rather then Moto X itself, but I wanted to leave my report.
I came from an S3, which suffered from the same problem when using Cyanogenmod. When using official Samsung ROM everything worked as it should. Now, I'm getting the same issue on my brand new Moto X.
When I try to call someone, sometimes it just doesn't call, after I press the dial button, it just hangs (without ringing) and finished the call with a "Cal ended" message. It happens randomly, and sometimes I can't call anybody for like 2/3 hours.
The simcard has been changed from the S3 (micro) to the Moto X (nano), so it's probably not it. Also, with the Samsung ROM it didn't happen.
I can still receive calls and messages, and the signal strength is fine most of the time. I just can't call.
Today I faced this problem and then I tried calling from my girlfriend smartphone (samsung ace IIx) at the same time, which is from the same carrier, calling to the same number, and it just worked fine. Mine still didn't work though.
Here is a thread on people on xda facing the same problem, but with a different phone: http://forum.xda-developers.com/showthread.php?t=2351227
Don't know what to do.
Click to expand...
Click to collapse

Call Ended Issue Resolved
Hi All,
I see this Call Ended Issue in many brands. So I assume the error is a combination of the Network along with the SimSlot.
I tried various combinations for my Moto-E mobile.
Before i post the solution i found, Let me provide a brief about the problem.
I use Vodafone network on sim1 slot and Uninor network on Sim2 slot. I started facing the call ended issue on my sim 1 vodafone network.
I inter changed the sim's and found the network working absolutely fine. This makes me to understand that the sim1 slot with the vodafone carrier has some network issue where that IMEI code has some problem.
i tried to place the vodafone sim again on the sim 1 slot and found the problem persists. So i came to that conclusion.
Hope this might help you and provide a instantaneous and temporary resolution.
Thanks,
Praveen.

Call Ended problem still going...
Hey,
I just rooted my Moto X (XT 1053), like 5 min ago, in the hope to fix this same problem. I`m no programer/developer and have nothing against rooting, I just don`t think I`m that kind of user. Anyway, about a week ago my phone started to drop my calls right after dialing. I restored factory settings, updated it and nothing worked. I took it for service and they offered to charge me 150 bucks to restore factory settings and update the software. So I was kinda forced to root and try to fix it this way. The problem is that I probably don`t understand half of what you guys say, so if there are any kind souls out there, please help me out.
To sum it up:
- No Sim Card error
- I get carrier services and can use mobile internet (3G because 4G is still too explensive here in Brazil)
- Directly drops my calls
- Won't receive calls
- Won't send or receive text messages via carrier (just over 3G or wifi)
I`ve tried another carrier's Sim Card, no go.
I`ve tried my Sim Card on another phone and it worked just dandy, so I really don`t think it`s carrier related.
I`m running Android 4.4.3, as the other updates weren`t available for my phone via Motorola. I thought maybe updating to a newer version of Android might do the trick. I just have no clue on how to do that on a rooted phone... or on a non rooted phone for that matter.
Can anyone give me any tips/pointers/etc... ?
Thanks!

I have the same issue with my moto x on Verizon. Have you been able to figure it out?

Question S21 Ultra sometimes doesn't show that someone is calling me

Hello,
For many months I have had a strange problem with my S21 Ultra, namely it does not seem to show me at random times that someone is calling me, no matter if via the cellular network or some communicators, it simply does not show notifications that someone is calling no matter how is calling. I often have it that only when I pick up the phone, unlock it and check something on it, suddenly messages come that someone tried to communicate with me, and only from then on I can answer calls until I hang up the phone and in an hour or two the same problem - over and over again. I have such an impression as if the phone itself went into some hibernation after putting away, although I have no indications that something like this is happening, because everything looks normal. The phone has the latest update, and I have restarted it several times with no effect.
I would like to add that this happens both in an apartment where I have wifi turned on (I do not use lte calls), and when I am outside while walking in the city.
Is there something I can do to fix this?

This is a very strange issue indeed. Have you checked if your phone has cell coverage when the screen is off? Did you try calling yourself from another phone and number? If the answer is negative to either question, I would suggest resetting your network settings. If that fails, try a factory reset which should solve any issues. If the issue still persists, it could be hardware related and you might need to take the phone to Samsung centre to get it checked.

I don't have a second phone to call myself. Friends say that on their end it sounds like I am not answering the call (i.e. they have a call signal, but just nobody is answering). They have no busy or unavailable signal. What exactly do you mean by a network reset, what would I exactly have to do? I was thinking about a factory reset, but I'm afraid that I will lose all my data and application settings. I do not know if it matters, but I have been using this phone since the premiere of the S21 Ultra, and when I bought it, I transferred all data via the data migration service from the previous S10+ phone, to which a few years ago I similarly transferred data from the S9+, to which I transferred data from S8 + earlier

Maybe you have the "do not disturb" option on? When I have this on, I can't see who is calling me.

I checked, unfortunately it's not that, if it were, I would never see someone calling, but my problem seems to be random.

Sierra76 said:
I don't have a second phone to call myself. Friends say that on their end it sounds like I am not answering the call (i.e. they have a call signal, but just nobody is answering). They have no busy or unavailable signal. What exactly do you mean by a network reset, what would I exactly have to do? I was thinking about a factory reset, but I'm afraid that I will lose all my data and application settings. I do not know if it matters, but I have been using this phone since the premiere of the S21 Ultra, and when I bought it, I transferred all data via the data migration service from the previous S10+ phone, to which a few years ago I similarly transferred data from the S9+, to which I transferred data from S8 + earlier
Click to expand...
Click to collapse
u need to go to settings>general>reset and there tap reset network settings..

Hi,
I experience very similar problem. I tried to reset network settings, "hard" reset the phone, playing around different mobile network settings... nothing helps. I'm not sure if it is phone hibernation issue or kind of removal of the phone from cellular antenna.
I have another phone I use to watch this s21ultra issue. Practically each day it happens that the s21 ultra does not react to my call, of course most of the time it works properly, but there are some tries, when it fails. In such case on the phone I call from I get a message "user is not available". But then, leaving the s21ultra untouched for 10 minutes I get SMS saying that someone tried to contact me, so it is not obvious that the phone hibernated.
I was not able to reproduce the problem on the other sim card put in s21ultra (the carrier is different). I was not able to reproduce the problem on the other phone and the sim card from taken from s21ultra. In my opinion it is related to "weak" mobile signal and kind of "sensitivity" of s21ultra to low signal quality.
I reported the problem to my mobile network provider, but I'm still waiting for the answer. Anyway, I'm going to do the following:
- ask for sim card replacement (cheapest option),
- (if above does not help) go to samsung service and ask to check the phone - I hope they have some diagnostics tools,
- (if above does not help) install the second sim card (from different provider) and configure redirection of calls in case of "user unavailable" - I know it is "stupid" solution - but at least one of the carrier should work
- optionally root the phone - Can anyone confirm if it may help? At least I could enable toggling airplane mode each minute