DoCoMo — TA Mdeals

I cannot understand what they(Tata docomo people) are doing everyday 15rs without any reason. Whenever my phone gets network first time in a day. I receive 3 smses from ta-mdeals with content "hi! Get additional 10% off on bill of rs.500 & above for buying any product on www.Starcj.Com. Your discount code is:[protected].Coupon expires in 24hrs. Tnc apply. " And guess what i have lost my rs.15 without doing anything... And [protected]@tatadocomo is fab they keep on saying that u hv done this and this.. Without accepting the fact that he is been facing some serious problem and why the hell do you think that i will dial that ussd again and again.. kindly suggest solution