Byju's — not accepting cancellation request

On[protected], byju's counsellor had booked a session with us for my brother. He convinced us to buy the product for 6th to 10th class. He asked us to pay 70, 000 which includes 1000 down-payment and the rest of the amount would be taken as loan. I paid the down payment and my aadhar card and pan card details were taken.
My loan amount was disbursed on[protected] even before i got the product. Now, i called them back to cancel the product as my brother wasn't really satisfied with it and nor us but was not able to reach them for a long time. Finally when i got in contact with them, they are refusing to take it back and i'll have to pay ₹5000 emi amount for nothing.
I just want them to take back their product which was barely used and cancel the course and loan also.