They used to call me every other day and say "sir aap koi internet use kar rahe hain" and no matter how many times I told them never call again they kept calling.
So I thought of a strategy.. I asked for the name of the caller and told him to connect me to his supervisor ..and this was a woman .. I asked her name .. I asked her position at airtel..
I told her that I will sue their company for harassing me.. .she never told her position..But the calls stopped even the automated calls that sell ringtones stopped.. try it..