Hi Robsto,
Welcome to Community! When a duplicate entry has been made in QuickBooks Online, you'll have the option to void or delete it from your books. I'd be happy to help!
Please keep in mind that voiding or deleting a transaction is permanent and can't be undone. If an item is removed in error, you'll need to re-create it. Here's how to delete a duplicate journal entry;
1. From the left menu, open +New and select Journal entry
2. Click on the history icon in the top left (looks like a clock)
3. Hit View more
4. Locate the duplicate journal entry in the list and click on it to expand the view
5. Scroll to the bottom and open More
6. Select Delete
That's it!
Feel free to reach out again with any other questions. We're always glad to assist!
