In order to refresh materialized view, this package, DBMS_MVIEW, is being invoked.
DBMS_MVIEW.REFRESH-Refreshes one or more materialized views
DBMS_MVIEW.REFRESH_ALL_MVIEWS-Refreshes all materialized views
DBMS_MVIEW.REFRESH_DEPENDENT-Refreshes all table-based
Make sure the user has privileges to this.