Airtel — Offer not received

Address:

Kolkata, West Bengal

I bought a Samsung Duos S2 phone online from flipkart (WS Retail). In the product display it was written that airtel will give FREE 1 GB 3G data per month for 2 months when a new airtel SIM is installed in this phone. This offer was valid till 30th Sept'14.
I purchased airtel SIM No: [protected] on 1st Sept'14 & activated it. But nothing free has come to my SIM.
Pls let me know how are you going to fulfil your commitment for the Free offer.
Pls give the offer to my above no. SIM urgently.
-Gopika Charan Sinha