No airline ticket, specially Indigo, lists any information regarding cancellation policy/ method thereof online. Passenger is required to call Indigo to cancel and cancellation charges, even 7 days prior to flight are so high that it’s not worthwhile to cance.
My example- bought 2 return tickets- Mumbai - Chandigarh for Rs 10088. Cancelation charges Rs 1500 per ticket, per leg amounting to Rs 6000. Besides cancellation fee & convenience charge of Rs 275x4. What does a passenger get as a refund? Less than a quarter of his payment. So decided to forego that too without journey.