Wacom Cintiq 13HD Pen has trouble switching between pen and eraser ends

Hi! So I use my Cintiq 13HD tablet frequently with Photoshop and Toon Boom Harmony, and in both programs I have this issue with the Cintiq pen. Usually to switch between brush and eraser, I simply flip the pen from the pen side to the eraser side, but now for whatever reason, that doesn't work a quarter of the time. I'll use the brush, flip the pen, and then the eraser just behaves like the brush - or the other way around, where the brush end will behave like an eraser. I have to flip the pen over and over again until it behaves the way I want it to. Workable, but an annoying waste of time.

I've already reinstalled the Wacom driver, and I've deleted and re-added my pen in Wacom Tablet Properties. I've also made sure to open Toon Boom/Photoshop before plugging the tablet in, because otherwise the program acts very glitchy and slow for some reason until I restart the computer (I guess that's another problem). Any ideas how to fix this?

Computer model: G751JL

Computer software: Windows 10 Home

Cintiq model: Cintiq 13 HD

Wacom driver version: Windows - Driver 6.3.32-4

Photoshop CC 2018 and Toon Boom Harmony Premium 16 if it helps