I've also had this happen a few times, the cause is that the main wheels are retracted too far and it therefore loses contact with the ground when starting up (wheels spin). Simply switch off the Mova completely (press the power button for about 10 seconds), then wait briefly and restart (press the power button again for 10 seconds). Then the height setting will probably reset and it will start up again. This has always worked for me so far. But it's still annoying, of course, and doesn't exactly fulfil the promise of "doing everything by itself" ...

Have you tried switching off the Mova and restarting it? It may also help to switch off the power to the docking station. Otherwise I wouldn't have any more ideas. Good luck!