Route part occurrence with missing relation to Catalog part
The route part occurrence in the model does not have the required relation to the part definition in the Catalog.
Part object is missing from the Catalog.
Display and modification of the affected feature will be limited until the situation is corrected. You will not be able to generate Isometric drawings if this relation is missing.
What You Should Do
Make sure the Catalog is correct, and then run DBI Clean, which will create the needed relation.