PPOM plugin bug

The bug can be find on the checkout.
after we add to cart the product along with the addons and change the quantity of the product, the addons on the cart total does not apply to the second product.
for example
Product 1 cost $100 then the addons cost $20, then after you change the quantity into two the total price should be $240. however the total price is $220 only. does not apply the addons for the second product.