Opener with RITTO 6721 (connection diagram available)

Hi everyone,

Sorry for posting the question again but I’m still having trouble with my opener. In my flat the Ritto 6721 is installed. I did a minimal wiring according to the screenshots attached (connected yellow cable to PIN 15, blue cable to PIN21 and the purple cable to PIN 0). I can still use all functions of the intercom system normally (ringing, door opening, voice communication). Though ringing and opening of the door does not work from the Nuki-App.
As this model is not listed within the Nuki-app I tried to configure it as a Generic - Analog model. Unfortunately the Nuki-Setup-Routine finishes with “Configuration failed”.

Is my wiring correct? Do you have an idea what might be wrong?

Thanks + Best regards
Michael