Brightness glitch

Phone : Android Asus Zenphone 2 ZE551ML.

Hello, I had set my Brightness setting to 1 for playing an horror map but now, when I want to turn it back to 100, it work only while I don't quit the settings, if I quit the settings menu, the brightness set it lonely to 1. I tryed with others levels of brightness but every time the same issue (it turn back to 1).