Consumer Redressal

During the offer period I have ordered a product from ShopClues my order no is :36051629 . the order got confirmed since I have made the payment and it was in the stage of shipping and suddenly I found the order has been canceled by shopClues. Now I would like to know how could they can cancel the order. And when I enquire they told they has some mistake in pricing so they are canceling the order. but when you have made the offer and customer has purchased they cannot canceled the order. Once I have bought a trimmer from then where they were showing MRP : 1000 Rs but offer price was 285 and when I received the product the MRP was 285 so that time I have got cheated. now if they have wrongly made the price and I have paid for the same I request them to ship the product.