Hi,
I can not only assure you that the service recall works on the T6, I can even prove it.
I actually have one myself. Please don't claim things that are not true.
The service reminder reset on the T6 does not work through the reset assistant, but exactly as described in the instructions within VCDS.
It's not actually an "error message," but rather a guide on what to do.
See also:
Okay, I'm ready. Please provide the German text you want me to translate.
Your instrument cluster utilizes diagnostics via UDS, as described in the text.
Best regards, Rainer.