Product tax calculation is incorrect

Product tax calculation is incorrect

Just trying out zoho and really surprised that I find this problem.

For invoices and quotes, I add a product.
List price £10, VAT (20%) tax is on that product and it puts tax of £2 on that item line.
But when it comes to the tax total, it's adding 20% again (an extra £2.40).

Something isn't right here.

Can you explain?