There was an error when saving a Invoice. QuickBooks error message: The document number has been used in another transaction.
Check and verify any "document numbers" IE: Invoice numbers have not already been used in QuickBooks.
In most situations QuickBooks Desktop allows duplicate numbers such as invoice numbers. If this alert pops up find and make the appropriate change to any counter we send to QuickBooks.
Retry the alert and verify integrity of the posted record.