That’s such a general statement. Flipkart is now specialized at doing this whether it be a metro city. Order a phone and they will delay it to an extent and you choose to cancel it and that is exactly what they want because they cannot fulfill the order.
Call flipkart executives and even they won’t be able tell you why is it not packed or shipped after 15 days.
Cases like this happens mostly when you bought them in sale in discounts.