Not detecting strokes from drawing tablet

[otterfree]

The tablet I'm trying to use is a XP-PEN pen tablet. All web app versions don't detect when I try to draw, but it does detect clicks on tools. Instead of drawing, the canvas starts scrolling in the direction I'm trying to draw. The problem doesn't seem to be the tablet, since other apps are detecting strokes.

EDIT: the problem seems to be with firefox? Strange since aggie works on firefox... but when I use edge the program works fine, although the strokes are in a different place from my pen.