How to block a lost Kotak Mahindra credit card immediately?

I closed my HDFC card last year. The process took exactly 7 days. They sent a confirmation email and a closure letter by speed post. Tip: pay off the full outstanding and request closure only AFTER the payment reflects. Calling repeatedly with a zero balance is the fastest path.

I have had a hard time getting this card approved twice. The third time I applied after a 10% salary hike and got instant approval. Banks re-check eligibility every time. If you got rejected, improve your income proof / CIBIL and reapply after 6 months.