A locker administrator is trying to remove a user account from the ownership of an...

The locker administrator is by default the administrator of the control room with which the locker is associated and as such can edit the locker permissions as an administrator and remove the user from the control room

Add a different user as the owner to the locker and then the user's account gets highlighted for selection and then deletion

Ask the administrator of the control room to delete the user's account

Ask the locker manager to edit the locker and take away the user account's privileges on this locker