Hey so I have already had to trade this iPhone in for a new one because the microphone didn't work in the first one, now for some reason out of nowhere my phone has decided to stop letting me make calls or allowing people to call me. I have done nothing to it except charge it and then I tried to call someone and it just sat there at "Calling mobile" until I heard three beeps and it stopped. People have tried to call me and it didn't work either, they said there was one ring then thats it. I just plugged it into my computer and it is up to date, I tried turning it off and on again, then a soft restart. And now, when I try to call someone and it doesn't work, I put the "End Call" button, the button goes gray but the screen stays on that call. I push the button to go to the main menu and the green bar is at the top telling me I am still on a call. Any help?