Warning (MS WORD): "Bereich kann nicht bearbeitet werden."

Warning (MS WORD): “Bereich kann nicht bearbeitet werden.”

Every time I want to insert a reference from EndNote 20 to Microsoft Word I get the warning “Bereich kann nicht bearbeitet werden”. After clickin OK, the reference is imported to Word. BUT the formating of the reference is not working at all. It looks like this {Author, Year, #905} but it should look like this: (Author, Year).

I already deinstalled and reinstalled Mendeley.

I also checked the Endnote-license: it is still active.

Any suggesions?

Best regards