This is a new Cloud customer with v6.12. They tried to delete a file as DWAdmin and got an error message: Lock for document with ID 235755 failed.
It was duplicated using another account that had delete permission.
However I attempted and succeeded at deleting the file without fail. I've tried to duplicate the issue by copying a file, opening it up usuing a 2nd account, and then attempted to delete using the DWAdmin account. No issue and it deleted even as the file was opened, in view by the 2nd account.