After a while you may notice the main panel and TS1 touchscreens have sensitivity issues, and may enter the wrong digit then the one you are trying to push, or may otherwise become non-responsive.

Solution: Its time to clean and calibrate the screens. Takes a few minutes, and is easy.

I recommend using a clean dry micro fiber cloth. Clean it just like you would your phone/tablet device.

I hear a stylus gives a more precise calbration, but a pen cap works just as well. Touch the center of cross near dead center.

First, disable screen, so it can be cleaned.
Security>menu>toolbox>enter master user code>clean screen

Calibrate screen.
Security>menu>toolbox>enter master user code>calibrate touch screen