Myntra.com — My order was cancelled by Myntra

I order 5 Jeans and 1 Shirt from Levis Branding. Some of the order were 2 day deliveries but just a day before delivery they cancelled my order on their own saying that it was out of stock! But when i checked it, and it was AVAILABLE at much higher price. Why Myntra is scheming in such a way? In fact I’m an Insider member! I am totally disappointed in Myntra Service towards its customers! Also i am not able to connect to their executive personnels! This is totally unacceptable.