Flipkart - Package not delivered

I had bought a Skybag trolley **cm from Flipkart on ** July **** during the offer time at a price ****.The order was supposed to be delivered on ** July but it got postponed to ** July.Again the delivery date got postponed to * Aug which they again postponed to * Aug because the product has not yet been packed or shipped till date.Meanwhile I called Flipkart lot of time but didn't get any answer from them.They blamed everything on seller and said can't do anything from our end.I repeatedly called Flipkart but got same answer again and again.At end they are asking me to cancel the order and re order the same product.The same product now costs **** .When I asked for the amount difference compensation ,they denied it completely and said to cancel the order completely.Initially I couldn't cancel the order as it was clubbed with other items as well .soon the offer period got over ,they gave the option to cancel the order.
It's been too frustrating for me since * days and till now haven't got any resolution nor they showed any concern.Evertime I asked them to transfer the call to seniors ,they disconnect the call and give a reason of technical issue.why should I be responsible for the seller,it's the flipkart who should be responsible for everything.why should I suffer.I have been mentally harassed .