The clean up operation was successfully initiated, but did not complete within the specified time. It is still running and ...

The clean up operation was successfully initiated, but did not complete within  the specified time.  It is still running and may still complete successfully. You can track its progress by viewing the system log (Source FailoverClustering) and the Microsoft-Windows-FailoverClustering-Operational applications and services log using Event Viewer on the node.