Harassment by Airtel

Hello, I was using Airtel # 9910025658 when I was in India. In December”2013 I decided to move to Canada and went to Airtel Store in Dwarka Sec-4, New Delhi to change my post paid number to a prepaid. The executive asked me that I need to fill out a form and submit ID proof. Also, I have to make the entire outstanding payment. I submitted the documents. The executive told me that the outstanding balance is of INR 950/- and I made the said payment on Dec 24th 2013 at Airtel Store. I received a new sim card and was told that this card will be activated in 24 hrs. Next day after I waited for 24hrs I called the customer care to confirm that why my prepaid sim is not yet activated. I was told that I still have balance of INR 430 on my account. I made the payment online Transaction ID# 1225603995 on 25th Dec 2013. After that the executive confirmed that I have no pending balance on my account and my pre-paid sim would be activated soon and post paid connection would be deactivated. I left for Canada on Dec 26th 2013 and by then my pre-paid sim was not active. But I didn’t bother much. But after my arrival in Canada, Airtel started the harassment of my family. First they started calling my mom and asked for bill payment. She told them that there should be no bill since I made the final payment on Dec25th and haven’t used phone after that. But they kept calling her and at times the guy misbehaved with her. When my mom stopped taking their calls they started calling the alternate number on my account. That number belongs to my sister. Right now Airtel executives call her everyday. They talk to her rudely and misbehave with her every. First we thought they would understand but it seems they do not understand. This harassment must stop now or else I am filing a case against Airtel for Mental Harassment of the consumer.