Airtel/wap services
Illegal deduction of money

I hold airtel prepaid connection... my no is 919002689670... 6/7 months ago an sms came to my phone saying"Thanks for using (fusion lounge, multicontent pack) subscription service on airtel wap.you've been charged Rs-15"from 64611015... although i didn't use this service... not only this... this sms came to me every fortnight and Rs-15 is deducted... I called up customer care... They responded and promised to fix it... but did nothing...