Airtel Mobile Bill — They are thretning, harrasment and illegal use of skip tracing

I was using an Airtel Mobil, when i was in delhi. Due to some financial problems i was unable to make payments for this bill. Now they illegally finds my number. They called one of my friend who is in Bangalore and said that we are calling u from a courier company and we want to contact Mr Shishir S Shankar, so she gave my number to them. When i received call from [protected] on 30TH of july lady over the phone was rude and when i was trying to explain them the reason for delinquency she transfered the call to one of the gentle man who started abusing me and was threatening me. Today on 31st july also i received call from [protected] lop was rude and was saying that they will sue me. Now I urge u people ti guide me because if they will continue to threaten me or harras me what should i do should i kill my self. Already i am jobless and trying to settle my messed up life. Please reply me asap

Yours Faithfully
Shishir S Shankar