Phone call ends if power button used to turn off screen when headphone is used

[Lbesze]

Just recently I had to start to use headphones[wired] due the speakers/earpiece being damaged or deteriorated, in other words they low on volume output and distort heavily. Anyway by using headphones to make a call the screen remains since it's not against your face so to turn it off one hits ithe power button, but that terminates the call as well. I went through all the settings, and I can't find anything related to it.Anyone using wired headsets to make phone call and have this issue, or if anyone have a fix for this?
Thanks!

 

[N4Newbie]

I don't know about your phone specifically, but in recent versions of stock Android OS, go to Settings -> Accessibility -> Power button ends call.