Indigo Airlines — Unfair trade practice

Address:

Indore, Madhya Pradesh, 452002

I planned a tour to kullu manali with my family in the month of march as it was school vacation for kids. for concessional booking in hotels and flights, i booked my tickets on[protected] that is one month prior to travelling.
i booked both tickets that is from indore to delhi and return delhi to indore in advance for myself, my wife, daughter and my son.
as my son's date of birth is[protected], at the time of booking ticket with indigo, the age of my son was below 2 years .and at the time of booking ticket the age was mentioned by me .
the total fare was calculated for both journey came to 22556, in which infant fare was calculated by indigo official site was 2000 for both journey.
i paid the same amount as calculated by the site and i confirmed the booking .
when travelling with indigo from indore to delhi it was a good experience as my son was irritating while in the flight, but the air hostess took good care and served chocolates and biscuits to my son and behaved very well.i was really impressed by the behaviour of the attenders.
when i completed my tour from manali, and get back to delhi airport,
i showed the same ticket to the counter for boarding pass, but at the ticket counter i was asked for 12611 rupees difference fare of my son.
i was shocked,
when i asked the clarification of the difference amount, the person at the ticket counter said that my son is above 2 years that is 2years and 6 days on the date of travelling from delhi to indore .
he also asked me to pay fare as per travelling date that is peak hours rate that was 12611 rupees.
i asked the person at ticket counter to help in this regard as i am innocent and i have already booked the ticket one month prior for return fare also by disclosing all the facts and age of my son., but all in vain.
the person at ticket counter asked me to hurry as the flight was ready to take off, in hurry i paid the same amount and ran to the boarding gate by taking both my childrens and my wife.
i was the last one to board the flight. it was very terryfing moment for me as if my missed that flight i would have to purchase the next day tickets for all the 4 members and book hotel for stay as well.
as all money was already spent in the tour, it would be very typical for me to manage my family members in that situation.
while in the flight an sms was recieved to me from indigo about sharing the experience travelling with indigo.
i messaged at once that it was a bitter experience for me travelling with indigo.
the next morning there was a call from indigo, why i shared the bitter experience.
i shared the whole event, but no proper reply was made to me by the officials.
Please look in to this matter and kindly refund my hard earned money back.
Thanks and regards
Mohit goyal
[protected]