Deleting a combo group
You cannot delete a combo group that is currently referenced by any other component (such as job, policy, rule set, or condition). You must clear these references manually before the combo group can be deleted successfully. When a combo group is deleted, all the member devices are no longer members of the group.
Logged events associated with the deleted combo group are retained (until aged out) and remain viewable in the Events viewer. The same is true of jobs that ran on the deleted combo group; such completed jobs are retained until purged and their detailed results remain viewable.
Do the following:
On the Network > Spans > Combo Groups page, click Delete 
in the Actions icons for the required combo group.
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