My backflip froze in the middle of a phone call. The touch screen wouldn't "touch" anything. The keys weren't active. The power button wouldn't turn the phone off either. So, I took the battery out and the phone went black (like it should). I put the battery back in and the phone would vibrate once and the green light behind the USB charger thing would flash on, but then turn off quickly. The screen is black. Nothing works. I don't know what to do.