Indigo Airlines — need refund for the mistake made by indigo airlines

Hi team, on friday (20th mar) i tried to book tickets (Ref number:xktnxj) in the flight (6e-411) scheduled for mar 22nd.
It clearly stated "hold cancelled" and my tickets got cancelled.
Meanwhile my account was debited with rs 12, 221.

After that, i went ahead and booked another ticket in the same flight (Pnr:sjr1qz).

Please let me know how to get the refund. Now i see that the cancelled ticket is somehow confirmed with pnr (:diy12j).

I reported for the same to indigo airlines on their customer service portal, but i didn't got any reply regarding the same for closing the problem with positivity.