Does this issue happen no matter where you are ? I’m wondering if it’s a Network Mast Issue with calls.
As a process of elimination can you please try your Sim Card in another phone to see if it occurs in another phone.
Also if possible try another active Sim Card in your phone.
If the issue continues and your sim works fine in another phone and the alternative sim in your phone still freezes on calls then my suggestions would be to carry out the following self help troubleshooting processes.
- Shut the phone down and then follow a set of button presses to enter into the phones file system and clear the phone system cache.
- Back-Up and Factory Reset.
- Find your most local Samsung Service Location or Samsung Experience Store for a diagnostic. Tell them what you’ve carried out with testing with SIM cards.
Daily Driver > Samsung Galaxy s²³ Ultra 512Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
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