Unwanted activation of service and deduction of balance

Location/place: jaipur

Name of company/service: tata docomo

sir,
evertime i recharge my mobile, tata docomo people activate some service on it without my permission, and deduct my balance, when i call on the customer care, and ask them that i didnt acitvate any service please refund my money, they simply deny, or they hung up the phone. This is pathetic sir, i am a student, and i cant bear these many mobile expenses, please help me sir. I am tired of these unwanted activations and deductions.
Regards,
Shreya Sharma