For about a week now my phone has been displaying no bars of service, but does not display a "no service" message like it has in the past. It does not ring or acknowledge inbound calls, nor will it dial on outbound calls. Texting has been fine. I have tried turning the phone on and off and this seems to provide an extremely temporary solution. After about 30 minutes, the bars disappear again and I can not make or receive phone calls, even with wifi calling on.