Welcome to the Community space, @Zippy33. I'll provide details and outline the steps to remove duplicate deposits in your QuickBooks Online (QBO).

If this happened on your Banking page and you categorized the deposit, you'll want to undo it and consider matching the bank deposit to the transaction. By doing so, duplicates will not appear in your QBO company. These are the steps:

1. Access your QuickBooks Online company.
2. On the left navigational bar, click the Transactions tab and select Bank Transactions.
3. In the Categorized tab, look for the deposit transaction and then click Undo below the Action column. The transaction will then be reverted back to the For review tab.
4. In the For review tab, click on the deposit and then toggle the Radio button beside Match.
5. Choose the correct transaction and then click the Match button.

For visual reference, see the screenshot below.

Another workaround is to check the bank register in your chart of accounts and from there. Locate the duplicate transaction and manually delete it.

To prevent this situation from happening in the future, double-check each transaction that goes into your QBO account before categorizing them. By doing so, you can spot possible copies of those bank transactions and exclude them.

Furthermore, you can visit this handy article to help you reconcile bank accounts in QBO: Reconcile an account in QuickBooks Online.

Need assistance managing multiple transactions inside your QBO company? Our QuickBooks Live Expert Assisted can offer tips and guide you to streamline the process of handling this task.

I am here to help you with your QuickBooks questions, so feel free to use the comment section. I can promptly respond and help you with bank deposit concerns. Keep safe.