QuickBooks Online sync error: Invoice XXXX cannot be created in QuickBooks Online - Invalid Reference Id : Product/Service assigned to this transaction has been deleted. Before you can modify this transaction, you must restore XXXX (deleted)
Why the sync error occurs
This error occurs when an invoice is trying to sync to QuickBooks Online from Key CashFlow, but a product or service on the invoice has been deleted in QuickBooks Online.
How to fix the sync error
Check QuickBooks Online for all the products and services listed on the invoice and make sure they're active. If you're not able to find a deleted item, the link between QuickBooks Online and Key CashFlow may be broken. Please contact Customer Support to relink the item.