MarketPress wrong tax calculation

MarketPress doesn't seem to calculate the total price correctly when the tax is applied with shipping on a product.
https://cdn.livechat-static.com/api/file/v2/lc/att-old/8801096/8b557cc1d69709482022c6f258048e5d/Single%20item%20checkout%20with%20tax%20on%20shipping.jpg

There should be a 20% VAT included along the 1.50 shipping.