A heads up on your situation with receiving phone call ringing. There are three reset options on a Android. Reset network, reset settings which I think is what you need to do first, and factory reset. You might have a tainted app and should be reestablished by sending it back to the store where it came from but first it has to be all permissions taken away starting with the bottom and working way up and this takes cash data out for one. Last thing is for stop and the app will on occasion try to stay in the phone. It has to be sent out of the phone and back to the store to restart it with all the permissions back again and try the runtime on it and see if it works. I have done this with factory apps and I was successful.
