I just got a new Artist 12 Tablet and Pen, and I'm using Krita to learn digital art. I realized that in Krita, the eraser end of my pen paints, and doesn't erase. I know the set eraser mode keyboard shortcut is E, and I tried programming the eraser tip in the tablet settings to the eraser mode shortcut, but the setting is permanently in "Eraser." Is it Krita not working right? Because everything else works seamlessly, just not this.

You have to select an eraser preset with the eraser tip of your stylus; Krita will then switch to the eraser when you flip the stylus.