As long as the first ignition is running after coding, the VZE works perfectly. As soon as the ignition is pressed a second time, exactly what you describe happens.
I have that problem too. I just couldn't figure out what it was. Since there is no error in the error memory, there must still be something missing from the digital AI.
With analog AI, this error probably does not happen.
Maybe you could try the following.
Stg 17
adjustment
Enable traffic_sign_display_BAP
Enable traffic_sign_detection