Help phone shut down

[mosescase]

My phone keep truning it self off. I will be on it then when I hit the side button it dosnt come back on. Not like a power down but shut down like some one pulled the battery and the only way to get it to come back is to pull the battery and turn it on. Any ideas

 

[SUroot]

That seems more like black screen of death. Its actually on but completely frozen.

Usually I associate this issue with people modifying their phone. I have seen some here have it without modifying though.

Perhaps some specific details about your phone model and it's history?