[ovirt-users] cannot remove vm.

Hi, I have a problem. I try to remove a pool and than I remove every vm but one of this display the message "Cannot remove VM. Related operation is currently in progress. Please try again later." I try to unlock with this command PGPASSWORD=... /usr/share/ovirt-engine/setup/dbutils/unlock_entity.sh -t all -u engine but not working in /var/log/ovirt-engine/engine.log 2018-03-01 17:02:47,799+01 INFO [org.ovirt.engine.core.bll.RemoveVmCommand] (default task-33) [0217d710-afb6-4450-9897-02748d871aa1] Failed to Acquire Lock to object 'EngineLock:{exclusiveLocks='[d623ad44-a645-4fd0-9993-d21374e99eb5=VM]', sharedLocks=''}' 2018-03-01 17:02:47,799+01 WARN [org.ovirt.engine.core.bll.RemoveVmCommand] (default task-33) [0217d710-afb6-4450-9897-02748d871aa1] Validation of action 'RemoveVm' failed for user admin@internal-authz. Reasons: VAR__ACTION__REMOVE,VAR__TYPE__VM,ACTION_TYPE_FAILED_OBJECT_LOCKED please help thanks Nick