Unable to remove duplicate transactions in VAT Return

Hello there, lfordyce.

If you receive an error message that says "The transaction you are trying to edit has been deleted in QuickBooks Online" when deleting duplicate transactions in VAT returns, you can try these steps:

1. Go to the Transactions menu.
2. Select Bank transactions
3. Select the affected bank account
4. In the For Review tab, select the duplicate transactions
5. Select Exclude
6. In the Excluded tab, select the tick box to the left of the Date column to select all transactions
7. Select Delete 

QuickBooks may download duplicate transactions when you connect your bank and credit card accounts to online banking.

To help ensure that no VAT is missed or duplicated when reporting to HMRC, check out this article: VAT exceptions and reports.

For future reference, check this guide about the list of common VAT codes and how they are used on your sales and purchase forms: VAT codes in QuickBooks Online: A complete guide.

If you have further questions about VAT returns, let me know by commenting below. I want to ensure everything is taken care of.