Why can't I adjust my screen brightness

A

AC Question

Hey, I use a samsung galaxy J1 ace its about a year old and recently i installed two apps that were in charge of the notification bar and after i uninstalled them i noticed in the notification bar ( the original that comes with android system) that the quick tool thingy to adjust the brightness has changed and my screen wont adjust the brightness anymore??

My phone runs android 4.4.4

Please reply asap this is driving me insane!