20-02-2023 03:55 PM in
Have you spoken to O2 about this or tried the sim in another phone?
Also, could there be any accidental presses on the phone?
Lastly, you could have set the volume keys up to end the call and that's being pressed? Have a look at Answering and Ending Calls here: How to set up Call settings on Android phone | Samsung AFRICA_EN
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