[Resolved]  Indigo Airlines — booking system

On thursday, 14/11/2019, i attempted to book a flight with indigo from chennai to madurai. The flight was 6e 7195 departing chennai on the 17th november. The fare amount was 3019inr.
I proceeded through the booking procedure and paid using a bank transfer from my dcb bank account.
I immediately received 2 texts from indigo stating that the transfer had failed, the flight booking was unconfirmed and if any money had been transferred it would be returned to my bank account.
I received no further communication from indigo.
I proceeded to book the flight with another airline.
On saturday, 16th november, i checked my indigo app on my phone and noticed a confirmed booking for the attempted booking as above.
The money had been deducted from my bank account.
I approached the booking office at madurai airport who directed me to phone customer support.
I called customer support, at 6:13 on the 16th, and spoke to a female, who, after several minutes suggested she could not understand the nature of my query.
I recalled and spoke to a male at 6:37 on the 16th. I related the problem to him and suggested indigo refund the money for the airfare.
After several minutes of discussion, he did not pose any resolution and resorted to a mantra "do you want to cancel this booking; there will be penalty amounts deducted from the fare. The penalty will be 2451inr and we will refund 568inr". I accepted that i needed to cancel the flight but explained i expected a full refund.
I believe this is entirely unreasonable by indigo as i had accepted their text advice in good faith.