[Resolved]  SBI Tata Credit Card — SBI TATA credit card - Cheated me

While leaving India in 2007 I called customer care and asked my card balance to pay the balance before leaving, I submited the cheque for the amount told by customer care. After one month of leaving India I again called them to make sure that I do not have any balance to pay them, once again customer care confirmed that there is no balance. approx after an year I visited India and found that I have a balance of approx 4000/RS. when I asked customer care they told that there was a balance of RS 300 on my credit card on which they were applying late fee and Interest and now my balance is 4000, I requested customer care regarding this and asked to wave of the other fee because I was told that there is no balance, but they did not give any, They are still adding interest on my 4000 and one day they will make a good amount by cheating me. I am looking for some online consumer forum who can take action against these kind of fraud.
Here my open questions are:1) Why I was told twice that I dont have any balance to pay.
2) Why I was not informed via mail or other comunication channal that I am beeing charged for a fee and interest.
3)why they did not deactivated my card instead of charging continous fine for more than one year and keeping it active.