Flipkart — Air ticket

I booked a flight ticket for my friend on 26 Jul 2021. The details of the flight ticket was attached here.
The travel date is SAT, 07 AUG ‘21.
The Friday evening my friend got the call from British airways and they asked him to change the airline (The phone was lifted by his wife the conversation was recorded.
She doesn't know English and she is unable to communicate his husband on that short notice to cancel and re-book the with other airlines.
At the airport, after being issued the boarding pass they denied his travel (boarding passes are attached here.)
We approached Flipkart and they pay back us a very minimal amount and the details were attached here.
We are demanding here with payback to us with hole amount since there is no mistake from my side.
We are approaching Consumer Complaints, hope the issue will resolved.