I've had my ace for 6 months now and recently I've started having trouble calling and people can't reach me. Trying to make a call all that happens is I get a single *beep* and the call is disconnected. People trying to call me get the same thing they don't even get sent to voicemail. Problem fixes itself if I restart the phone for a while but usually is back within a few hours. I live right next to an antenna so that ain't the problem either. Anyone got a clue what could be the problem?