Byju's — Cancellation & Refund

I would like to inform that I have purchased a course from Byju's and gave them advanced Rs 5k. They have clearly mentioned that if I am cancel it within 15 days they will refund my amount. I have canceled it within 15 days and communicated through mail but even after 15 days still no communication from their end not only that I got a phone call from Byjus that the will be going to deduct EMI from next month. Sales person from Byjus Aritra Dutta not responding since last 15 days.