ORA-29388: plan/consumer_group string is part of more than one top-plan
Cause: An attempt was made to delete a subtree that includes a plan or consumer group that is part of more than one top-plan as part of procedure DELETE_PLAN_CASCADE or package DBMS_RESOURCE_MANAGER. Such a plan or consumer group cannot be deleted
Action: Check the ancestors of the plan or consumer group and make sure it is only part of the top-plan that includes the subtree being deleted
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