[Resolved]  Citibank Credit Cards — Default

I had two citibank credit cards for several years since 2000, whose payments were made regularly. In 2003, on one card, there was a fradulent transaction made by someone else on internet (the transaction originated from outside India, and I was in India). The transaction came to my notice immediately, and the next day, I notified Citibank help line.
Subsequent to that, I complained several times to Citibank, via Fax to their head office, helpline nos, and telephone calls. AFTER Three months, I was told by citibank that they cannot reverse the transaction and I have to pay, as I did not notify them in time. When I told them that I had notified them the next day, they said complaint has to be filed in a prescribed form (which I was not told for a period of three months). I told the bank helpline that I shall not make the payment of 20000/- (legitimate outstanding on other citibank card) and the card in question till the entry is reversed.
After that for several years, I did not hear from citibank, and no statement was received by me. in 2007, I shifted my residence also.
No I get calls from Citibank agents for repayment of several Lacs of RS. I dispute this matter and do not agree. But the bank has put my name in defaulters list. I would like to resolve the dispute. Please advise.