ZARA No Refund Due on Wrong Items Delivered Internet

Apparently it is alright for a company to not reinburse you when they send you an incorrect product you did NOT order.  Even though  you return it following the instructions on the the returns slip that include the options of returning the item because it was the wrong item send.  Supposedly somewhere obscurely in the terms and conditions I was supposed to follow different instructions then those on the return slip.  INCLUDE THOSE INSTRUCTIONS ON THE RETURN SLIP IF YOU WANT THEM FOLLOWED!!!!!   Don't make me pay for your mistake!