ORA-23477: unable to alter propagation mode

admin

ORA-23477: unable to alter propagation mode for object group "string"."string"
Cause: The propagationmethod of a materialized view object group can only be
altered when no other object groups with the same master object group aresharing
the materialized view site.
Action: Ensure that there areno other materialized view object groups at the local
site with the same master object group.