Unable to delete Snapshots on SnapLock volume Error "Snapshot operation not allowed on a read-only volume"

Applies to

ONTAP 9.0 and above

Issue

• Unable to delete Snapshot on SnapLock volume 

Cluster::> snapshot delete -vserver <vserver> -volume <volume> -snapshot <snapshot>
Warning: Deleting a Snapshot copy permanently removes any data that is stored only in that Snapshot copy. Are you sure you want to delete Snapshot copy
         "<snapshot>" for volume "<volume>" in Vserver "I<vserver>" ? {y|n}: y
Error: command failed: Failed to delete snapshot "<snapshot>" of volume "<volume>" on Vserver "<vserver>". Reason: Snapshot operation not allowed on a read-only volume.

• Below error in snaplock-volume.xml proves that SnapLock state is inconsistent:

Error "Unknown...inconsistent SnapLock Snapshot state"

• The below command shows the SnapLock volume in an Unknown...inconsistent state

::*> vol snaplock show -vserver <vserver> -volume * -fields expiry-time vserver volume expiry-time