HP India — hp laptops back to college offer

I have purchased a laptop from the hp store on july 4th, 2019 with back to college offer which said we get bang & olufsen headphones worth 25000 rupees for an extra 2999 with the purchased laptop which i did pay (54000=2999). Now its more than 4 months and i haven't received the headphones yet. Customer service is of no use. Whenever i call them to the redemption cell (So-called their offer redemption contact center) they always say it takes another 15days. This happened to me more than 3 times. Now they are not at all responding about this. I contacted the hp customer service too but they came up saying this is not the redemption team and i have to contact the redemption team which is of no use as they keep saying another 15 days and that's it. I have all the proofs of claim approval and everything.
Kindly help.