All Brightness Sliders/Settings Gone

I just noticed that any way to change my brightness for my laptop has gone. And it's currently stuck on max brightness, which hurts my eyes.

Usually the function buttons on the keyboard will do the trick, or the sliders in the taskbar/Control panel.

But suddenly it disappeared

I've checked out other posts and I can't seem to find any with the same situation.




Even the brightness slider on the mobility center isn't functioning too.

Thanks.

PS btw am I posting in the right thread?