Good day, @SCS14,
You can search invoices paid by your client through the Merchant Service Center.
Here are the steps to follow in searching for transactions:
Please check this out for additional information: Search for transactions in the Merchant Service Center.
Our merchant care team can also help you if you need further assistance viewing your invoices. You can reach them out through here: https://community.intuit.com/browse/payments-contact-us.
If you have any other questions, please don't hesitate to ask and I'm always here to help.