My initial guess is that this could have been a “mis calibrated” servo, with the arm at the wrong angle, but since it’s one of ours, I would now suspect that it is just a bad servo. If so, please contact customer service via email for a replacement.
One other thing to check, if you are able to, would be to try raising and lowering the pen between those same values from within Inkscape (ideally on a desktop computer). If it still fails in the same way, you can be sure that it’s a matter of hardware failure rather than of something in the software setup or parameters in the CLI.
