This happened to me yesterday and i found out how to solve it!!!!!!!
The only bad thig is you will lose everything from your phone

1.wait 5 mins when your phone has fully tuned on(if you turned it off)
2.get a diffrent phone and call your self
3.when it appers that you have a call, in the bootom of the screen you will see reply with message or something like that. slide it open
4.after you did that hit the home butten
5.(now wait the problem is not solved because if you leave it like that it will go back to how it was) .after you have it the home button quickly go to settings and go to pravacy and factory reset it
6.after that you problems are solved
Keep in mind everything will be erased
hope you found this helpfull i found this out