This QuickBooks Desktop conflict occurs when Method tries to post a payment to a transaction that either:
can't be found.
has already been paid in full via another payment record.
If you encounter this conflict, you'll see an error message that starts with:
QuickBooks returned an error when adding/modifying a accReceivePayment record.
How did the Conflict Occur?
There are a few ways this conflict can be triggered:
The payment was created in both Method and QuickBooks while the sync was not running. When Method tries to sync the payment to QuickBooks, it finds a duplicate payment. (This is the most common way this conflict is triggered.)
The payment was created in Method and linked to the appropriate transaction, but was not synced with QuickBooks. The transaction was then deleted, but the payment remains.
Faulty customization attempted to pay a transaction that was already fully paid.
How To Fix this Conflict?
In order to fix this conflict, the user will have to determine whether the payment record is a duplicate, or whether the invoice balance has already been paid.
If the payment record can safely be deleted, you can delete the conflict in your Sync Conflicts screen (which you can access by going to Profile Icon → Integrations → QuickBooks Sync → Sync Conflicts).