I have updated to latest versions of everything. Still same problems:
Right after installing or modifying some things, it works both for add-to-cart and fill_cart. Unfortunately if I delete the coupons and products in that order, fill_cart won’t add the products if the same url is used and add-to-cart won’t apply the coupons.
So the only way I have found is first use add-to-car, the fill_cart, the remove one unit of the product. Any idea of what could be happening?? :/ :/