Indigo Airlines — Not allow to board in the flight without any reason

Address: Ranchi, Jharkhand

I have booked a ticket from ranchi to bengaluru for 1st april, which check in time is 2:05 pm, i reach to ranchi airport and check in at 1:45 pm but the authority say you are late and can't board for flight. I ask them what is the reason for stopping me, they say your are late and tell me that if you want another ticket of tommorrow then you have to paid rs 3000 extra. Is this the new number to cheat the people by indigo.
Flight no - 6e 5325
Pnr number - m7vc65
Journey date - 01/04/2017