Airtel — my airtel number doesn't catch network in usa

Address: Pune, Maharashtra, 412101

Hi,

My airtel number is [protected] but the sim card doesnt seem to be working here (In the us) as it is not able to detect the local us network, can i get some help as i need to be receiving msgs, else there is no point in having an india number, when i bought the sim card i was told that it would work globally, this needs to be reolved at the earliest. I have tried selecting the netwrok manually and in automatic manual.

Regards,
Tushar