[ovirt-users] Disk stuck initializing

I created a extra disk to attach to a VM, which I used for several months. When it was time to remove it (as I intended to replace it) I managed to detach it, but before I could remove it I got it stuck in with status "initializing". I wish to delete this disk, as I'm done using it, but all options are grayed out in the UI. The disk is not attached to any anything. The underlying storage domain, which is running GlusterFS across the 3 oVirt hypervisors is showing no issues. Several other disks are running on with no issues. The only thing I could find in the engine log was 2019-05-09 17:03:39,693+02 INFO [org.ovirt.engine.core.bll.storage.disk.image.TransferDiskImageCommand] (ServerService Thread Pool -- 72) [d3615da6-823c-4421-ad00-6d8060b8b291] Lock Acquired to object 'EngineLock:{exclusiveLocks='', sharedLocks='[0498e532-a1de-4281-953d-7dec31271437=DISK]'}' What can I do to clean this up and free the used space? Best regards, Mikael