Diagnosis
You want to set or delete the production resource/tool indicator (PRTID) for the document type (FHMKz).
You can only change this indicator if no documents of this documenttype have been created yet.
As documents of this document type already exist, you cannot remove orset the indicator in this situation.

Procedure
Define a new document type if required.
If you really want to change the indicator for this document type, allexisting documents of this type must first be deleted.