Location/place: delhi

Name of company/service: airtel

Hi
I am using airtel prepaid since last 5 yrs. In the recent 2 months, I am facing this problem when my prepaid balance is getting deducted automatically.Rs. 6 gets deducted 2-3 times every day as a result my balance reduces to 0.On my complaint Customer care representative told that the rs. 6 is being charged for internet usage, but I am not using it at all..

please help !!