We can override the sales tax amounts in two ways, gcci1963. We can either enter an adjustment when making a tax payment, or create a sales tax item.
If you choose the first option, you can use this article on how to enter the adjustments on the tax payments: Record, Delete, or Edit a Sales Tax Payment.
If you choose the second one, you can refer to this article on how to create the sales tax item: Enter Sales Tax Amount Manually.
You might also want to browse this article to know more about Automated Sales Tax.
I'll be around if you have more questions about it. Have a great day!