Indigo Airlines — Not departed by airlines

Address: New Delhi, Delhi, 110014

Website: INDIGO

I had planned a emergency travel with my 8year son from delhi to kolkata on 29th dec 2016 for a personal emergency.I had reached the airport well i time at 7.00 am for a flight scheduled at 8.20am however even after issuance of boarding pass and security check in the ground staff did not announce on boarding and when i checked with them at 8.00am they said boarding gates closed.I was not allowed to board and hence to miss my flight.I had to bear a loss as cancellation would not get any refund.And they also charged rs38000/ for next flight.
Please find the passenger details below:

name:ananya sarkar
pnr no:acdujq
date:29/12/2016
flight no:6e 377
name:shourajit sarkar
along with me and my son 1 others passenger were not allowed to board as there was no announcement for boarding and even after checking on time they said boarding gates closed and passenger full.
Please help me in refunding the ticket amount.
Thanks