Engine for vents above, discovered below

Hey, guys.

I have now broken down the panel on the driver's side due to the airing problem (5min), then you can see the actuator (behind the center console, quite below)
The wonderful works if you e.g. on -air only medium duesen- only up- -only down-.

Unfortunately, however, the bloed flap does not open for the middle Duesen.. What could be the problem here?
The last one, she just went up like that during the ride, and now she's not even a little violent...

Greeting
Bernd