Amazon India — Delivered product (Macbook air) has different serial number than mentioned in invoice

Address:	Gurgaon, Haryana, 122002
Website:	Amazon.in

The product (Macbook air) i received has different serial number than the serial numbe mentioned on the invoice.
Now i can't get insurance or extend warranty for my mac as i can't prove that this is my laptop. Moreover i can't report or file an fir in case of any theft or any other issue.
My warranty is about to expire in about a week and amazon hasn't even given dedicated support executive to the problem. Every time i call, i have to explain my problem to a new support person.

Please help. Macbook parts are real expensive if not in warranty.