Refused to refund

I went to gasoline store to buy jeans. I asked to fit the jeans and when i got to the fitting room i found out that the jeans button was poor quality so i requested for a proper one ( the same Design) and payed for it. The next day i discovered that it was not the same one as the one i chose, than i went back to the store for exchange and i ddnt get the right size for the design i want so i requested for my money back and they refused. I called their boss Named Nico he also refused to give me refund and now im stuck with jeans that i dont even like. And which is not my fault .