Airtel — Charges without using service

Dear Sir/Madam,

I am writing you this email to bring a serious concern about my Airtel bill for November month. In my recent airtel bill they have added additional charges of 414 rupees. This is some add on service activated on my number ([protected]) without my consent. I called the company and as the customer service mentioned that several SMS have been sent to 58234 number in every three hours from my mobile, even in the mid nights. We never sent any SMS from our mobile to particular this 58234.
I requested the customer service of Airtel to remove the charges but they denied it.
Therefore, I request to wave off the addition charges of these SMS which I never sent from my mobile.
Thank you in advance
Regards,
Kamlesh