Odd touchscreen issue

[mistafast Profile]

Apologies if this is not the website for a post like this

I recently got an fx-cp400 at the beginning of this year. Yesterday, the touchscreen stopped working, but the calculator has not been dropped or otherwise damaged. The weird thing about it is when the calculator is left alone and dims before automatically powering off, the touchscreen registers a touch and brightens again. I have already tried downgrading to version 2.01.2 to attempt a touchscreen recalibration, but there was no response. Updated back to current 2.01.7 and the problem still occurs. No matter where on the touchscreen is pressed, there is no input anywhere. I would greatly appreciate any tips or fixes, otherwise I will get it serviced. Thanks!