Error when editing Correspondence Received or Sent

We recently upgraded to Contract Management 13.1.2.03, Build 2461

We get the following error when trying to save a record in either the Correspondence Received or Sent modules.

"Could not save your changes to this Correspondence Received because another user edited it. If you want to make these changes to the latest version of the document, return to the log and edit the document again"

If the user returns to the log opens the record again and then edits the record and clicks save, it saves ok.

Has anyone had this issue, I would be grateful for any information you could provide