The Printer driver tries to read the address. There are cases where this interpretation is not possible for technical reasons. Depending on the circumstances, the error situation can be executed correctly, and a corresponding error message is displayed.
However, there might be situations where the address cannot be recognised. As a result, no correct address is displayed on the sidebar and the document split (in the case of a form letter) is not correct. Please check the declaration of the individual mail items (note: a declaration can also be made manually).