My phone had water damage, so tmobile did an exchange with a new one. I got my phone, and it worked well for about 12 hours. Then it suddenly stopped getting the t mobile signal. It said "searching", I've tried removing SIM card, checking if I got a new one w. the phone (I didn't), connecting manually to the network, and turning phone on & off. Wi-Fi will still work, but I cant make calls or send texts, says "no network" Any help would be amazing PLEASE.