1, restart the all-in-one machine: sometimes the pen tip is not allowed to be a small bug in the system, and shutting down and restarting can solve the problem.

2. Check the pen and nib: make sure that the pen and nib are intact. If the pen or nib is damaged in any way, it needs to be replaced.

3. Calibration pen: Some all-in-one machines have pen calibration function, so you can search for the related operation of "pen calibration of all-in-one educational machine" and perform calibration according to the steps.