Hi kat234,
Welcome to Community! QuickBooks Online automatically calculates the sales tax, based on the rates you've set up. However, it's vital that the associated sales tax is accurate on your forms, in keeping aligned with government guidelines. I can understand your concern with the unexpected outcome, and would be happy to point you in the right direction, so you can complete your QuickBooks goals with confidence!
Based on the details you've provided, I feel you would benefit more by contacting our Customer Care team 1-855-253-1536 from Monday to Friday between the hours of 9 AM and 8 PM EST. With your consent, they'll connect with you virtually and review the issue in more depth. In addition, they will be able to escalate it for further investigation with our Development Team, if necessary.
If you have any other questions, feel free to reach out. We would be glad to help!