If you have groups that are no longer used that need to be deleted and you do not have a policy in place to delete those groups dynamically, you can do so manually.
Delete groups
On the navbar, expand Identity Administration and select Groups.
Click the Delete Group(s) action.
Search for the group that you want to delete and then check the box on the returned group record.
Repeat step 3 for each group that you want to delete.
When ready, click Submit.
Click YES to confirm you want to delete the group(s); otherwise, click NO.
Click OK to close the Operation Execution Summary.
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