Please help

Guys I bought a sneaker of 1199 at Reebok on the 6 March the sneaker was delivered and fitted the shoe without checking whether the shoes was stained or what as it was delivered on my work door I did not even took the shoes with me to my house and I requested an exchange as the shoe is big for size 7 instead of 8 now was told the shoe was stained they won't exchange the shoe they such cruel company like Reebok