I have manually posted a deposit into QBO and now my bank has downloaded the deposit into QBO. Why is it duplicating vs matching?

Hello there, @elenorf12.

The bank transactions will be downloaded automatically, once you turn on online banking in QuickBooks. Manually posting an entry(deposit/payment) can cause duplicates.

To get this sorted out, remove the unnecessary figures and match the deposit to the corresponding sale transaction.

Here's how:

1. Click on Banking on the left pane.
2. Refer to the Banking section of the page.
3. Go to the For Review tab.
4. Put a check-mark the box next to each transaction you want to exclude.
5. Select the Batch action drop-down menu, and then hit on Exclude selected.

 After that, start matching your bank and QuickBooks transactions. To do that, you can refer to this link for more details and on how to fix online banking issues: Download, match, and categorize your bank transactions in QuickBooks Online.

I'm just a reply away if you have any other questions. I'll make sure you're taken care of. Have a great day!