Geeetech

I have had my I3B pro for about 6 months now and the knob used to control the LCD panel no longer works. I can control the LCD panel at all so I can no longer print via SD cards which is not good. How do I go about getting a new LCD unit since there is a 1 year warranty on this?

Is it sometimes working and sometimes not? maybe the set screw on the knob is loose, I found my knob not working two days ago and the screw was loose, maybe you can check it.
And where did you buy the printer?