Your CIBIL Score is not only dependent on your timely payments towards loans/credit cards that have been availed but also the amount that has been paid.
E.g. If you have a high credit utilization on a credit card and are making monthly minimum payments by the due date, this will not affect your payment history. However, this will impact your CIBIL Score as the minimum payments made is low in comon to the actual amount payable.
You can maintain your CIBIL Score by making timely payments every time, as well as ensuring you are paying off the balances on the loans/credit cards. Paying more than the minimum due will help bring down the total outstanding on the accounts.