HappyEasyGo.com Cheating — fare cheating

Address:

110070

My name is joji raju, i had to book a flight through www.happyeasygo.com on 14 dec 2017, which was for 2 adults, 1 child and 1 infant from delhi to trivandrum.
The rate shown in their website was 2543 as you can see that in the attachment. While doing the final payment they have added rs. 250 per passenger as their convenience fees.
Even if they add rs. 250 with 2543 the final amount for an adult comes around rs. 2793.
So the final figure should be 2793 x 3= 8379, but the final payment they took is 11172/- which i could not understand at all.
Then i requested them for a receipt of the same with the figure for each passengers, which they refused to provide, instead they said they will give only the total bill.
Then i approached the airlines, indigo to know what are the charges for an infant. Then they mailed me saying, they charge rs.1250 for an infant. Even after adding 1250 with the adults and child fare the total amount comes as 8379+1250=9629.
Now also i don't understand where is my 1543 has used. Its really a cheating and they are not at all ready to help me