This is an error that occasionally occurs during the sync:
- Processing payment for invoice: I160404529
ERROR OCCURRED: An application error has occurred while processing your request: System Failure Error: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; Premature end of file.
This error occurs if the payment was previously synced to your QuickBooks Online, but has since been deleted.
InvoiceASAP retains a link to the payment and is trying to update it.
But if that payment no longer exists, then this error message displays.
To resolve this error for a successful sync, delete the payments in InvoiceASAP and recreate them.
Deleting a payment in InvoiceASAP deletes the link to the now non-existent payment in QuickBooks Online.
And when you create a new payment, there is no link to the payment in QuickBooks Online, so the sync is able to run successfully.