I have a problem regarding delivery prices.
a) If I have two products with different delivery prices, the delivery prices add up (this is correct).
b) If I have at least one product with free shipping then automatically shipping is free for all products (whole order).
The expected outcome: I would like shipments to add up, regardless of whether a product is eligible for free shipping.
Is it a Presta bug?
Is there any way to fix it?