Glad that you've posted again, PuzzleCoffee.

Let me share the things that we can do to correct your filed tax in QuickBooks Online.

As my colleague suggested above, we're unable to remove or delete the filed tax in QuickBooks Online. Only the tax payment can be deleted within your account. With that, we'll need to contact our specialist first to help us unfile the tax for January and February. This way, we can make any changes from the report and start for a VAt adjustment.

Please consider following the steps provided by ChristieAnn. Here's the sample screenshot within our QuickBooks account. Let's take a look at this sample screenshot too:

Let me know if you have other questions. We are all right here to help. Take care!