I understand you already reached out to our customer support team, circletax1. 

I can see the urgency of fixing your tax rate to ensure the calculation is accurate in QuickBooks.  

In QuickBooks, the tax rate calculation is generally based on the three factors shared by my colleagues above. 

Since the issues you encounter with tax rates remain unresolved, I recommend contacting our customer support team again. They have access to the latest information and can provide detailed updates on the situation. Additionally, they can assist you in resolving the tax rate issue by offering solutions and troubleshooting steps. 

Here's how to connect with them:

1. Click the Help menu in the upper-right-hand corner and click Talk to a human.
2. Type in "Talk to a human," then press Enter.
3. Look for I still need a human and click on it.
4. Choose Get help from a human.
5. Pick between Start a chat or Get a callback.

In the meantime, as a workaround, we have two options to address the issue. One is to create a custom sales tax, allowing you to apply the appropriate tax rate to the transaction. The other option is to overwrite the existing sales tax amount in the "See the math" section on the invoice, which will enable us to manually input the correct tax amount.

1. From your invoice, click the See the math hyperlink to see the breakdown of the taxes.
2. Click the Override this amount hyperlink.
3. Enter the Rate column, select Other as the Reason, then click Confirm. 

For complete information about sales tax in your QuickBooks Online (QBO) account, refer to these articles.

• Learn how QuickBooks Online calculates sales tax
• Set up and use automated sales tax in QBO

Feel free to ask any follow-up questions by commenting below. I'll be here until you're able to fix the sales tax rate calculation. Have a great day!