Motorola L2
Not compatible with Airtel

I am an airtel customer. I purchased one moto l2 on 22-02-07 form day 3 it started giving message limited service. In network menu airtel was not available. While the vendor is extremely cooperative, he told that the system is only 4 bsnl. These things were neither told to me nor i was given the free bsnl prepaid connection on purchase date. Subsequently he has given it, but how does it solve my problem with airtel compatibility.