Comelit 6228/DE in Simplebus 1 Mode

Hello,

I have a Comelit 6228/DE. This device supports Simplebus 1 and 2. It is running in Simplebus 1 Mode.
As far as I read, Simplebus 1 should be working.

Nuki lists the 2608 as compatible which uses simplebus1.
I also read that Comelit 2708w/a is working (which also uses simplebus1)

I am able to install the opener and also to configure the first steps.
So the opener recognizes the opener signal and also the ring signal from the street.
But it is not able to open the door via the app.

Any ideas?
This device also uses simplebus1.
So I don’t understand why some simplebus1 devices work, while others not.

Thank you