Airtel
Very very poor and delay response

I have taken internet connection with land line telephone connection. I don't how one day, music portal subscription activated and 30 rs extra is added to bill. Even after this I paid 30 Rs. for some months and on aug 24th i gave muisc portal deactivation letter to airtel office. But yet it's not deactivated ane still 30 Rs. extra is comming in my bill.