After trying to delete the cluster logging operator add-ons and error appears:

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Add-on `Cluster Logging Operator` has been deleting for longer than 2 hours on cluster `Cluster_ID`

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It seems that the pods are gone from the `openshift-logging` namespace and the operator is back to the list of available add-ons on Operator Hub, but the CLO add-on in OCM doesn't reflect this since there is an `add-on failed` status so it's not possible to install it again.