[Resolved]  Nokia / E71 — airtel free internet offer

Dear Forum Members,
I have just purchased a NOKIA E72 on 17/12/09. On the set top it is mentioned that i will get 100MB of free internet download each month for three months. here is the offer, printed on cover box of nokia e72 handset.
'Airtel offers 100 MB/month internet browsing free for 3 months with select handsets.
If you want to get this offer send SMS 'My Data' to 543210 from your handset. 100MB free data download per month will be credited in customer's account within 24 hrs of receiving the SMS. Please note that this offer is available only for Airtel subscribers who own the following handsets. This offer is valid from October 2009 to December 2009 and customer will be charged at 30paise/50KB forpost free MB usage.". I received confirmatory activation message from airtel. But as I went onto browse i am being charged for web surfing. I have tried talking to airtel customer care and nokia customer care. Airtel CC care siad they didnt know that such offer exists at all. Nokia customer care didnot receive any of my calls at all. I am registered customer of NOKIA with my mail ID: [protected]@yahoo.com. Please help.