My bank was purchased and merged; new transactions were brought into QuickBooks, but I think there are duplicates that were downloaded a second time from the new account.

Hi there, cappuccinoandco. 

Let me make it up to you by ensuring you'll be able to delete duplicate transactions in QuickBooks Online (QBO).

If these downloaded transactions are duplicates of what you already recorded in your books, you can Exclude them. I'll show you how:

1. Go to the Banking menu or Transactions menu.
2. Choose the For Review tab.
3. Click the checkbox of the transactions to exclude.
4. Select Exclude.

For the complete guide on excluding bank transactions, please see this article: Exclude a bank transaction you downloaded into QuickBooks Online.

I'm also adding these articles to help manage your bank transactions and keep your QuickBooks balance accurate:

• Categorize and match online bank transactions
• Reconcile an account

I'll be here if you still have questions or clarifications about managing your bank transactions in QBO. Have a great day!