Error 7012 with Datasource OPC UA Client: Username

I am using my PFC200 with the Datasource as OPC UA Client, but when I start the program, I get the error 7012: The username that is passed to the userconfiguration at runtime must be the same as the username passed in the Datasource configuration. In the Logs there is a message “diffring username at configuration and run time. vs. OpcUser” (with a empty space before the vs.)
OpcUser is the right user, I can see the login attempt in the OPC Server Logs, but no data is send. Where do I need to add the user?

I have tried different Security Settings (Policies and Modes) but the error is still the same. Certificates are valid and accepted on both ends. Reading the OPC variables from the server via Codesys works great.

Codesys V3.5 SP19 Patch 7
Wago PFC200 750-8212 04.05.10(27)