Could anyone please help me? I'v succesfully installed this contri in two webshops. One has been working great from the start on, but the other one is giving me trouble. When people go to the checkout_shipping page, they get an error message, about the shippingcosts being changed. (that's a piece of the languagefile language.php, in my case dutch.php: ENTRY_DISCOUNT_COUPON_SHIPPING_CALC_ERROR'). It seems to appear randomly, because when I test it now I don't see it, but other customers have seen it and weren't able to continue checking out because the error blocked it. Nothing in any file has changed after installing the contribution: no products have been editted, no shipping costs have change etc.
They did not use a coupon code: they didn't even get to the page where the coupon code is asked!
I've searched a lot but I can't find any solution, could anyone please help me out? Thanks a bunch!
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