Airtel Postpaid Mobile Connection — Harashing calling people from my caller list

Hi,

This is Navin Srivastava. I am airtel postpaid mobile connection user for the last one year. I have never done any default in the payment. This time I am out of India on my business trip and missed to pay the last 2 months bills in time.
Now the airtel execuitves from call center are calling people from my personal caller list and calling them and harashing them always to make the payment.
I am here to raise the concern that this way they are misusing my personal information. Without my concern they are pulling the numbers of my people from my detailed bill and calling them. I am scared if they would have distributed all the numbers to may be whom all.
Pls let me know the place where I can file a case against Airtel for stealing my personal information and harash my people using them.

Any suggestion would be highly appreciable.

Thanks
Navin