Hi, my k850 screen went blank as soon as I press the middle button like number5,4,6, and the down button.

everything still working, even if i press the touch button it registers, but the screen is black. except when i wait it to be in standby mode, then i can wake up the screen by pressing any button.
problem persists after restart.

hope u guys can help out and advice, thanks!

Hmm.. I think ur keypad spoil already..
Bro, are u sure RM 250?
if not mistaken, I change it early of the year only cost me RM 170