Allow me to help you get the list of all the refund receipts and get these transactions matched in QuickBooks Online.
To get the list of all the refund receipts, you can pull up and customer the Transaction List by Customer report.
After that, let's get these refunds matched.
You may find this article helpful: https://quickbooks.intuit.com/tutorials/lessons/refund-receipts/.
That's it! Hope I helped you get all straightened out today. Let me know if you have other questions about refund receipts in QuickBooks Online.