How to increase credit limit on Citibank credit card?

I had the same dilemma. The way I decided was: list down my top 3 monthly spend categories, calculate the rewards on each card, and pick whichever gives the highest cashback on MY pattern. Generic 'best card' lists are useless for personal decisions.

Dispute process that worked for me: I called customer care within 24 hours, raised a dispute via the netbanking portal (uploading the receipt showing I never visited the merchant), and got a provisional credit in 5 working days. Permanent credit came after the bank's investigation in about 30 days.