How do I unmatch a payment to an invoice to be able to match it to the correct payment?

I'll guide you in unlinking your payment, field-lance.

To do this, you'll want to click the 1 payment hypertext and the payment date. This will route you to the Receive payment page where you can unselect the invoice to unlink it from the payment.

To link the other payment transaction to your invoice, simply open it and select the invoice to be paid.

On the other hand, you can check for references for QBO by clicking on Help and searching for the topics that you need help with.

If you have other concerns, feel free to go back to this thread.