why would a fully charged HTC beats audio cell phone switch off and not restart

Bubbles1980

Estimable
Jul 29, 2014
2
0
4,510
My phone just switch off, it's fully charged and now I can't switch it back on and I can't
Open it at the back. Please assist?
 

Bubbles1980

Estimable
Jul 29, 2014
2
0
4,510

Hiya I used it about an hour before it switched off and everything was working fine, I went to use it again and it was dead. Tried charging it but won't come on. Thing is it was working perfectly fine and hour ago