Airtel Post Paid
SIM registration failure

I have an airtel post paid connect for lat 5 years. Two weeks before it suddenly stop functioning saying SIM registration failure. Even after repeatedly complying to the Customer Care all they could say that the problem would be resolve in 4 hours. Now it is almost 2 weeks I have also replaced my SIM by paying 150 Rs but still no result. Surprisingly airtel doesn't have a working Customer Care Number which we can call from a landline. I find it quite pathetic and advice all other it is better not to go for airtel.

Thanks,

Saji Pillai.