I have a HTC One M7 and when it goes into sleep mode won't wake up anymore ?

[AC Question]

I thought it was something with the battery level but last time it got into 56% and never woke up/ The only way to wake the cell up, is to plug the power cable and then the cell will start like someone turned it off previously.

Does any one know what this could be or what is causing this ?
Thanks.

 

[B. Diddy]

Welcome to Android Central! I wonder if the power button is faulty. Does the button work to power down the phone, then power it back on again?

 

[plabre75]

Power Button work but I believe theres something with the sleep mode....any ideas ?