I have been having this issue since I got the phone from verizon. Incoming calls will ring on the callers end but my phone will not ring. If they leave a message I will get the alert that I have voicemail but if they do not I will no idea that anyone has called. I have had the sim replaced and a replacement phone and it is still happening. I was told that it could be something I have installed on the phone. fair enough. I wiped the phone and started fresh and it is still happening. The interesting thing is I am on an account with 2 other people both with iPhones and they are not having this issue. Has anyone else had this happen?