BMPCC 4k touch screen issue

I bought my bmpcc4k last Sep, and today i found the buttons in the bottom area of touch screen not responding, is this a hardware problem?
At first i doubt it is some kind of system issue and i updated the firmware to 6.8.1, after that, i stuck at the 1st step "selecting language" because after making selection, the 'Submit' button is at the bottom of the screen, and it completely not working..
i wonder if i send the camera back to fix how long that will take, it took me 2 month waiting to get the camera which is very frustrating, i am really concerned how long will the fix take
At first i doubt it is some kind of system issue and i updated the firmware to 6.8.1, after that, i stuck at the 1st step "selecting language" because after making selection, the 'Submit' button is at the bottom of the screen, and it completely not working..

