My phone was working fine a few days ago. I did not get the phone wet, or damage it in any way.  
  When I try to answer incoming calls, the phone keeps vibrating like it is still ringing.
  When I try to make calls, the phone freezes until the call is 8 seconds in, and no sounds or ringing  
  Does anyone know what the problem could be?
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IPhone cannot accept or make calls?