Airtel Postpaid Mobile Connection Mob. No - [protected] — Prepaid balance not transfer in post paid bill

Dear Sir/Madam
My self Syed Faraz H. Zaidi Using Airtel Post Paid connection Mob. No. [protected] from 03/10/09. Before this date this No. was prepaid and that time this No. convert in to postpaid my prepaid account balance was around Rs 300, and at that time you did say to me that Rs 300 will be reduce from my post paid bill, I have get two bill and also have complain for that but this money not reduce in any bill.
So plz tell me how much time will you take for that problem

Thx & Reg
Syed Faraz H. Zaidi
Mob- [protected]