How to add new data groups to existing HCM Extract?

Summary:

I receive error while trying to add new data group to existing HCM Extract.

Content (required):

I have this structure and I just created the highlighted group:

It seems fine to me:

At the moment it has no link with other databases:

If I add the link I get this error:

If I try to save I get this other error:

I don't understand what is wrong

Version (include the version you are using, if applicable):

23B

Code Snippet (add any code snippets that support your topic, if applicable):