Brightness Control Gone ~!!

I have a Galaxy S5, it's working great with no problem since I've got it
but today the Brightness Control in the drop "notification" menu just disappeared !
and I did check the box in the notification panel setting !
I have no idea what happened and I really hope someone can help me :\

It's Ok I found the Solution for the Problem ,,, if anyone ever had the same issue, just download an app called "Night Mode" - Turn it on "Start" - and then turn it off "Stop" and it should be restored :D