Thank you for posting here in the Community, Scoobyjimbo.
I'd be glad to help the online program will calculate the correct VAT amount on your invoice.
Let's make sure to check if FRS (Flat Rate Scheme) is disabled. I'll show you how:
1. Go to Taxes from the left menu.
2. Click the Edit VAT dropdown and select Edit Settings.
3. Once done, click Save.
I've added screenshots for your reference.
If the issue persists, we can perform some troubleshooting steps to fix this. There are times when the browser is full of frequently accessed page resources, which causes some errors or unusual responses.
Let's start accessing your account using a different or private browser. You can use either of these shortcut keys:
If it works, switch back to your regular browser. Then, clear its cache. This way, you can access QuickBooks with a clean slate. You can also use a different supported one.
I've added this article to learn more about VAT codes in QuickBooks Online:
Feel free to hit that Reply button if you have additional questions about how VAT works in QuickBooks. Have a great day ahead.
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