Moving along full tablet height only moves cursor halfway up tablet screen (linux)

I have the working area set as follows:

 If I start with the stylus at the bottom of the tablet the cursor is correctly at the bottom of the screen, but then when I move the stylus up the cursor moves at half the speed it should and only reaches halfway up the screen.

If I change the settings to custom area of only half height like this:

I did notice that in xinput the transformation matrix looks potentially wrong but I tried editing it with xinput set-props but even though the command went through the values were the same/didn't update when i ran list-props again