Airtel — airtel international roaming sim not working

Airtel is one of the most horrible service providers in india.

I took an international roaming sim before i left india last year. I had to pay extra inorder to get quick sim activation.
But, the sim never worked thereafter even for 1 sec (After i left india). Every month last year, i received the bills which were more than basic rental amount. Still, i kept on paying my bills every month with the hope of the sim working when i land in india.
Last month when i went to india, the sim did not work. Thanks to airtel.

The customer support team was never helpful in resolving my problem, instead asked me to pay additional amount to close the account.

Every time i called the help desk, they just kept my call forwarding.

Huge dissatisfaction!!!