Double taxation when I let an option increase the price by percentage

Hey!

I have a woocommerce webshop where I have set that I enter product prices excluding VAT. On product pages the products are shown including VAT.

I am using the yith add-ons plugin to add options to products. When such an option adds a fixed price, it works perfectly. However, when this is a percentage, something goes wrong. For example; I set an option with an additional percentage of 50%. To determine the option price, the price including VAT * 50% is then done. VAT is then added to this, making the yith option price a double tax. This only happens in the Product Price on the product page. In the Shopping Cart, it does show the correct VAT calculation.

I want that when I set an additional cost as a percentage, it is done on the price excluding VAT as set in the shop.

Is this possible? I don’t see an option to set this anywhere and with php I can’t get it fixed.

Thanks in advance!

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