Thank you for getting back here in the Community, @ExpoCorey.
Let me share with you the steps to undo a sales tax return in QuickBooks Online:
Also, I'd be adding a helpful article that may help you when you want to set up, record, and track sales tax for products you sell in QuickBooks Online: Sales Tax in QuickBooks Online.
Don't hesitate to post a question below if you have other Sales Tax concerns. I'm always here to help. Take care always.