MakeMyTrip — Fraud while booking the tickets and refund

While booking the flight, MAKEMYTRIP charged Rs 2574 as taxes. Unfortunately I missed the flight. Airline is saying I was noshow for the flight and can only refund the tax amount which as per them is Rs 692/-. The booking ID is NF[protected].

Passenger Names Type Base Fare Taxes & Fees Total
Mohammad Waseem Akhtar Adult Rs. 3520 Rs. 2574 Rs. 6094

Payment Details
Total Fare Rs. 6,094
________________________________________
Total Amount Charged (rounded) Rs. 6,094

How can the tax be Rs 2574/- at the time of booking but Rs 692/- at the time of refund. MAKEMYTRIP is clearly doing some sort of fraud here. I tried to get an answer on this question of difference in tax amount while booking and refund, but MAKEMYTRIP did not provide answer, instead just kept on repeating the same thing again and again, saying airline tax is Rs 692/-.

I just hope no one else is cheated like me by these fraud websites.