Why is my HTC one's screen not showing up?

[AC Question]

I was using my phone and then all of a sudden it just froze and then i tried turning it off and now the screen is just black. But it's weird because it's still charging and everything. I tried to hold the power button but when I do the home and back icons just flash and nothing happens. Please help!!

 

[B. Diddy]

Welcome to Android Central! Which HTC One is it? M7, M8, M9? Or one of the earlier models?

Leave it plugged into a wall outlet overnight without disturbing it. Then try powering on by pressing and holding Power for at least 20 seconds.