Diagnosis
You assigned an object as a superordinate object, but according toCustomizing settings, this object is not allowed to be superior to thecurrent object.

System Response
The assignment cannot be saved in this form.
Possible reasons for this include:
The object you want as a superordingate object is not at a higherposition in the hierarchy then the current object.
The object you want as a superordingate object is in a completelydifferent hierarchy.
You skipped over one or more hierarchy levels.

Procedure
Assign a valid superordinate object to the current object.