Call failure immediately upon answering incoming call on iPhone 7.
When I answer an incoming call in my iPhone 7, the call immediately drops and I get a Call Failed notification. When I try to call the party back immediately, I hear ringing on my end but there is none on the recipient's end. It appears that both incomng calls and outgoing calls are not connecting. Never had any issues with the phone until now (after 14 months). Restarting the iPhone usually gets it working again.
I have already tried removing the sim for 5 mins and reinserting it. This did not permanently solved the problem. I have not tried resetting my iPhone...yet. The process scares me.