Thanks for providing further details, @Emancipare. Let me further assist you on this.

Based on the screenshot you've provided for Client A, the one that's attributed to your invoice is the payment with Paid status, and the sales receipt with Closed status could be a duplicate transaction since they have the same amount but different dates.

In QuickBooks Online (QBO), you can either choose invoices to record pay-later transactions or sales receipts for immediate payments. To resolve the issue of duplicate transactions, I recommend reviewing the sales receipts in question and delete them if you're using invoices to record sales, as they could lead to double counting of income. You can directly match the received payments afterward. Here are the steps:

First, let's run a Deposit detail report to identify the sales receipts at issue causing duplicate transactions.

1. In your QBO account, go to Reports.
2. Type in "Deposit detail" in the search bar and select the report. If applicable and convenient for you, choose Switch to the classic view.
3. Select the date range for the transactions you want to review.
4. Click on Run report.
5. Look for transactions with the same deposit date, amount, and customer name.

Next, if you've confirmed that the sales receipts at issue are duplicates to your invoices, you can follow these steps to delete them.

1. Go to the Sales menu.
2. Choose the All Sales tab.
3. Select Sales Receipt from the Type drop-down menu.
4. Once completed, choose the sales receipts that you want to delete.
5. From the gear icon beside the Actions column, click the drop-down.
6. Hit on Delete and confirm.

After this, when you go to the Bank transactions page, you can proceed to match old received payments from your invoices to your downloaded bank transactions. Just a heads up, I recommend consulting an accountant while performing the steps above to ensure having an accurate financial record.

Let me also add this guide about reconciling accounts after you've matched and categorized transactions in QBO: Reconcile an account in QuickBooks Online.

Let us know on the situation if the issue about duplicate sales transactions still hasn't been resolved on your end. We'll do our best to assist. Take care.