IMS Registration Keeps Stopping Samsung S10

[Andy7856]

Hi

Bit lost here please, the IMS registration keeps dropping every 24hrs.    Have factory reset, cleared the message cache, wiped the cache partition, updated all the software and apps, cleared network settings, SIM swapped.    Pretty much run out ideas.  O2 chat said speak to Samsung, Samsung said speak to O2.  O2 have re-provisioned my SIM but still drops out pretty much every 24hrs to the minute.  When I lose the IMS I also lose functions such as setting call divert, call awaiting etc, wifi calling etc, voicemail stops etc

I run a Samsung S10 on OXM firmware / Android 11.     It seems like the O2 network is kicking me off the IMS service every 24hr when perhaps the O2 network refreshes and thinks I am an "unauthorised" user.

Driving me wee bit nuts now...

[pgn]

Clearing IMS App and Messages App caches and a reboot might help, @Andy7856:

[Andy7856]

@pgn  hi thanks for the reply. I have tried that.  In my case I dont get any error message, like the one in the video, instead it simply shows "not registered" when I go via SIM status menus.    Reboot always brings it back for 24hrs before been kicked off again.  As I dont get any error messages I think its down to O2's system kicking me off the IMS service as opposed to a handset issue - but O2 cant find anything wrong with my account.   Very odd.

[pgn]

Sounds like O2 and your phone are in disagreement, yes, @Andy7856. I read something about an O2U version CSC, perhaps that might be the way to go?

https://www.sammobile.com/samsung/firmware/sm-g973f/O2U/#SM-G973F

Not unlike O2 to only permit some advanced functions with specific families of phone o/s, they did it for some of the OnePlus phones and 5G services too.

[Andy7856]

@pgn Hi, Think I cured  it!  am responding back to hopefully may guide someone with same problem at a later date that comes searching...

The issued seemed to be around the data connection,  making sure my phone always had the data switched on. more importantly with the correct data settings.  As I have been swapping SIM and generally messing about my data settings appeared to be the incorrect and legacy from the other network SIM..    Some networks appear to text you data settings, O2 appears to have them already on the SIM.  Anyway when I corrected the data settings it cured it.     So the error was staring me in the face all along! 

[pgn]

That is great news, @Andy7856 - glad you got it sorted, and that you could tie it into a repeatable root cause. 👍