cumulative tax

-- HikaShop version -- : HikaShop Business 4.5.1

Hello,

I've created a cumulative tax of 5.2% for a customer group. Once they have created an order with the two taxes specified on the invoice, sometimes they decide that they need to add a product after the order is created. When I add the product to the created order it doesn't break down correctly the VAT. Actually, it will add all the VAT (including the 5.2%) to the 21% VAT(main tax). To correct it I go into the database and modify the taxes in the "hikashop_order" table and the "order_tax_info"

Is there a solution to this problem?