HDFC Bank — Emi debited and not canceled

It's been 2 months since the amount got debited from my account for a Flipkart order. I have cancelled the product on May 29th. Flipkart has reversed back my money into the credit card ending ****5206. But the very next day the same amount got debited by the bank as EMI. I have contacted the customer helpline about 10times but there was never a response from the HDFC bank