Hi Mathew
Can you please share where the selling company is located? I guess it is US. Because of things like origin based and destination based pricing it would be interesting to know the state.
For tax calculation we use SoldTo, ShipTo, Company, ShipFrom, Account Type (corp./ private) and product type (material or service). Based on this Information the systems determines the tax country and tax code. In your case the tax country is wrong, so we also need the company tax country/ state.
Best regards and thanks
Marlene