[Resolved]  Vodafone — Faulty Bill

I have postpaid connection with Vodafone with number [protected]. Last Nov07 to July08, i continupusly received faulty bills. After that when i went for converting my post paid service to prepaid service they offered me a very lucrative offer of 2000 sms free of rent for first three month and then after rent of Rs 25 . But after first three months, i have received a bill of 2500 as they have charged for sms. Now they are flatly refusing and not correcting my bill. Need help . Thanks