product is not giving to me

hello sir i did a order for a 16gb memory that day there is offer so i will buy the card of 99rs and somewhat shipping charge but i paid online and order is confirmed but after two days i received order is cancled and they gave me refund but i wrote complaint but they are not giving me the product now they said the product of 450rs its fraud with me and said that time there mistook for the price thats why they are not giving the product …but i paid for the product and why they shows that product in offer 99rs only so please help me and solve i buyed from shopclues