MakeMyTrip India — Voucher not usable

I had done hotel booking using MMT and for that, I used Vouchers worth 10000 rupees also (Booking ID NH[protected]). I then cancelled that booking and tried to do a new booking. MMT site shows that the Vouchers are available but when I try to use that to my new booking, it says Voucher cannot be applied. There is no way to get the 10000 rupees back or use it to my new bookings. I tried unlinking/re-linking those vouchers but still its not working.

The customer care number doesn't allow me to talk to an agent, no email id is provided on the website. I need my 10000 rupees worth Voucher added as cash back to my wallet or I want MMT to refund 10000 rupees.