Flipkart.com - False information provided by customer support, in order to cheat the customer

I saw the offer on Flipkart.com for buying Google Pixel * xl rewarding rs **,*** cashback on citi bank credit/debit cards.
The relevant terms and conditions were :
the card must not be corporate and the offer is valid in India.

Now I was ordering the phone to be delivered on an Indian address but the Citibank card was issued in Singapore (the terms on Flipkart didn't say anything about the card issue location).

So I confirmed with the Flipkart team if I could avail this offer on my Singapore card. So they very confidently replied in the mail and also the call (I have evidences, see highlighted part in the attachment) that I could use my card as long as it is not corporate card.

So I went ahead and purchased the phone on (** feb ****) and I ended up paying more ***** (after currency conversion by Citi ) and the offer didn't apply and now suddenly the flipkart team knows that the offer is valid only for cards issued in india.

Not only this issues has cost me like rs ***** (***** cashback + **** conversion fee ) , they have harassed me mentally by not replying clearly enough and beating around the bush, every time I have to resend a mail to them asking for details.

When I contacted them, they said - "we confirmed the misleading information was given to you but we are sorry we can't help you on this issue."

Hope justice would be served.