Credit Information Bureau India [CIBIL] — my cibil report says severe delinquency

Hi i applied to citi bank credit card and they rejected it on 23 aug 2017 saying less credit score. I recieved my report which says in the scoringfactor
1. Too few satisfactory accounts
2. No presence of a revolving tradeline
3. Presence of severe delinquency in past 6 months.
The score is showing 676. Recently when i had checked 2 weeks back in credit mantri it was showing 718.
I have never missed a payment for credit card nor a loan and not even a single delayed payment. I want to know the reason for this scoring.