Mine died last night too.
It was 70-80% charged when I went to bed at about 0200, at 1015 I tried to turn it on and it wouldn't work. Tried charging and nothing; no light. Took the battery out and put it back in and then it started working.
I cannot have this happen again! I need to be in contact and have the alarm working.
Anyone know what might have happened?
yeah, I just had a similar thing happen to me. Went to unlock it and nothing. Took the battery back out and put it back in. Nothing. Took the battery out again and it finally turned on when I pressed the power button. Had 80% battery. Thought I was going to be making a trip to verizon.