Same issue, phone doesnt hang up and has issues answering a call. This problem has persisted for a month+ and it still hasn't been resolved. this should be a priority to fix the phone app for a phone
I have the same/similar problem on my S22. I get a black flashing screen when I try to hang up from a phone call. I can't swipe down on the top of the screen to access the call again, I just get another black flash over my screen and have to wait for the other person to hang up. I also just changed my settings to hang up using a side button, though suspect I'll accidentally hang up on people with that. That isn't a real fix. Samsung needs to send out an update to fix this issue or recall cell phones that have it.