A couple weeks ago, my phone completely turned off and wouldn't turn on for about fifteen minutes. After that, my phone barely gets any service, txt messages take forever to send and receive, and when I try calling anyone, it won't do it at all. My calls also get dropped often. I know its not the service because most of the people that I live in the same building with that have the same service have no problems what so ever. Is there anything I can do to solve all these problems?