Auth Code Innogy

most of the items of my smart home are Innogy-Items.
Since some weeks I’m not able to get an connection between OH2 and Innogy.
I’m running the latest version (2.5.8) of OH2 and of the binding.
When I generate an auth-code with the link(s) from the documentation the smarthome controller tells me, that the auth-code is invalid and I should generate a new one. But it doesn’t help to generate a new one.
I’ve also cleaned the cache, but no change.
Any ideas how to solve it?

Thank you in advance for the help!

This is the link I’m using to generate an auth-code: