[Resolved]  State Bank of India — Wrong Interest Calculation

Address:

Chennai, Tamil Nadu

I'm using SBI credit card for past 1 and half years. 3 months back I made two balance transfers to my HDFC and CITI bank credit cards. And two months back I made one more BT to my HDFC credit card. When I called SBI customer care for this BT facility, they didn't give enough information on how the interest is calculated. When I see the statement on October 15th, I was totally shocked. What they said is, it is calculated as day basis. But they didn't tell the formula to get the interest amount. I tried myself and got somewhat nearer amount as they mentioned. I paid partial amount on 31st of October. Again today (16th of November) I received the latest statement. In that also the interest amount mentioned is different from as I expected. The customer care people also doesn't know how it is calculated. If I request for interest calculation sheet (usually you can get it from other banks), they are saying we don't have such future. How should I get the proper information from SBI credit card?
Summary:
15/08/2012 - BT to HDFC Bank - Rs.20000
15/08/2012 - BT to CITI Bank - Rs.15000
17/09/2012 - BT to HDFC Bank - Rs.55500
03/10/2012 - Paid - Rs.3000
15/10/2012 - Interest calculated - Rs.2072.66 + 12.36% Service Tax
31/10/2012 - Paid - 26798.84
15/11/2012 - Interest calculated - Rs.1329.39 + 12.36% Service Tax
Please help me.