Amazon India - Order not received yet

Recently I had placed an order for Apple Iphone** on *th June ****, while placing the order, the arrival date for this package was between **th-**th June, which was almost a week late.
Assuming that as its a rare colour it might take that much time, from **th they moved the date to **th June for arrival. Entire day I was eagerly waiting for my parcel, by then at around **pm I received an msg stating that as they were unable to reach me , my parcel was returned.

next day i.e from **th june till this morning , i have nearly *-* calls everyday to your customer care, tried to chat and get a solution for my problem but everyone just kept saying the same line that "wait till today evening i will receive my parcel for sure as it is out for delivery".

I have also made calls to the delivery guy myself to track the parcel, he said in the next ** mins he will come , since yesterday, i have been waiting for him.

Is this the way a Prime member is treated? Is this the way an escalation department senior handles the problem or closes it by not even ensuring if the customer has received the parcel on time or not. What is the benefit for being a Prime member or forget even a Prime member, is this the way a customer is treated?
I guess I made a mistake by ordering it from Amazon instead of walking to the showroom.

I hope this reaches you, I get some satisfactory response .