samsung s2 turns off everytime I try to unlock the phone

[thosa]

Hi there,
I have a samsung s2 that turns off on its own every time I try to unlock the screen. Then it just vibrates till I start it back up again. I've only been using the phone for a bit two months and there is nothing wrong with the battery as far as I can tell. Does anyone have any advice?

 

[rgd1101]

try take the battery out and put it back in.