Hi palmsy71,
The invoice error stating the tax rate was not applied typically occurs when the session loading QuickBooks resources is interrupted. To solve this, simply click the Save and close button again after receiving the error to successfully save the invoice.
We can also try refreshing the page by clicking the Refresh icon in the upper-left corner of your browser or pressing F5 on your keyboard. This will restart the session and reload QuickBooks Online resources.
Alternatively, you may use a different browser. Just ensure it is up-to-date and compatible with QuickBooks Online.
Feel free to comment below if you need further assistance or have additional questions.
