TDI Injector Problems: Golf 7 Variant 1.6 CXXB

We have this error message on this Golf, as shown in the picture, and we're not sure what to do next.

We have replaced a differential pressure sensor because regeneration was not possible before, which is now working again.
According to the inspection plan from Otis, the AGR (Automatic Gear Retarder) should be tested, but the test seems to be failing or stopping prematurely without a result.
The function test with VCDS indicates that everything is okay.
We compared the actual and target values using a reference vehicle, and they were almost identical.

Hey, you're a customer of the competition.

For such cases, I can offer:
https://shop.dieselschrauber.org/en/obd-support-key-p-112.php

That's it for now.

Best regards, Rainer.