power button not working for booting.. but opening lid does?

My HP250 power button won't turn it on but instead works for forced shutdown or hibernation/sleep purposes only. the only way I'm able to switch on the laptop is to remove all power sources that being the battery or adapter cable then after I would close the lid and place back battery or adapter cable, when I open the lid that's when the laptop boots into windows. I have also resorted to force shut it down because every time after shutdown it automatically restarts.

what could be the cause of this ?

I have already tried a couple of those electrostatic discharge methods for the power button to work.