The amount which you paid was clearly for Settlement which is the account is still showing a balance of Rs.10,000/. To close the account and get a NDC letter you need to pay the remaining balance to Citibank.

After you make the payment, the bank will take approximately 45 - 60 days to get the status updated in the bureau. You need to check your report after the stipulated time. Also, in the meantime, please use your other credit card properly. If you have a loan make sure you making regular payments on it. This will help you to build you credit score side by side.