cannot decrease the brightness of g2 korean

[AC Question]

what might be the problem if i cannot decrease the brightness level?

 

[B. Diddy]

Welcome to Android Central! Are you able to access the brightness setting? Does the slider move at all? Does it move but the brightness doesn't change?

You may need to consider a factory reset. I'd suggest a cache partition wipe, but LG phones generally don't allow the user to do that (in an unrooted phone, anyway).