The option to delete a submitted or filed return is currently unavailable in QuickBooks Online (QBO). You'll need to contact our Phone Support team so they can create a VAT unfiling request to remove the incorrect one. Before doing so, please prepare the following information:
QuickBooks Online Company ID.
Which tax filing period you wish to unfile.
Here's how to reach them:
In QBO, click the Help (question mark) icon at the top right.
Select Contact Us at the bottom to connect with our live support.