Monitor, power button on, black screen

My monitor screen remains black while monitor power button still in standby mode no matter how I press the button it won't turn off.

I disconnect the power cord behind and leave it for I think more than a week and then put power back on but no floating dialog box appears the power button is lit on standby mode.

Will this be the end of life for this monitor, no way to be fixed anymore? 

thank you.