Amazon.in - Promised Citibank Cashback of Rs.2000 not Given

I had ordered Lenovo G**-** **-inch Laptop (Order No: ***-*******-*******) and before ordering, I was promised cashback of Rs.**** on **st October, **** from Amazon.in when my payment got declined on **th October, ****.

But today on *th February, **** after *** days, customer representative says I am not eligible for Rs. **** cashback on Laptop because Citibank cashback payment is eligible only for * Citibank card per account and that I had used my cashback eligibility on **th October, **** for ordering an IFB microwave owen. This eligibility requirement of using only for * Citibank card per account is not present in Amazon Citibank Cashback T&Cs and also in Citibank Cashback T&Cs. Amazon claims it is in some FAQs. How is customer supposed to know it will be in FAQs when it isn't present in T&Cs.

Moreover, my transaction got declined on **th October,**** and I had to do it again on **st October,****. Naturally, I had doubts over cashback eligibility for **st October,**** as it was valid only till **th October,**** and I asked Amazon for confirmation on the same and I got a written confirmation over email from an
Amazon agent that I will be receiving Rs.**** cashback for Laptop also. Now, how can Amazon refuse to give me cashback for the Laptop? If I wasn't getting the cashback, I wouldn't have paid for the Laptop again on **st October after my payment got declined on **th October.

Don't you think this is unfair on Amazon's part to cheat customers like this? I expect my situation is considered seriously and my cashback of Rs.**** is compensated by some means at the earliest.

I am attaching the mail conversations with Amazon customer representative on **st October for your reference below where he promises me of Rs.**** cashback for Laptop to be received by January **th. Also please refer to Amazon Citibank Cashback T&Cs for **th October,**** to **th October,****

Thanks & Regards,
Shivram