Why the Sync Error occurs
This error occurs when a manual payment has a reference number (Ref#) that is already in use in QuickBooks or a manual payment has a Ref# when it is for multiple invoice payments.
How to Fix the Sync Error
There are two options to resolve this issue:
- If the issue is due to a single invoice, edit the payment to update the Ref# to a unique number ~ or ~
- If the issue is due to multiple invoices, edit the payment to remove the Ref#