When mobile company is deducting our balance without informing us and than do not give credit ! sply Airtel?

Airtel has deducted my 99 rupees and on enquiry they say i have game downloaded but i had no download and i am innocent even than they didnt credit my amount..this happened on5.3.11 and immidiately i talk to customer care but they refuse to credit me.....this is just loot and rape on customers.|||you need legal advice