Indigo Airlines — Flight not caught how ever boarding pass issued

Address: Ghaziabad, Uttar Pradesh

Sir My Flight from Delhi to Raipur today and i got boarding pass at 6: 30 My flight departure time is 7:30. When we sent on gate for departure at 7:17 the ground staff told that the gate closecd before 20 minute from departure and we are unable to caught the flight. We are only 2 minute late & we suffer a great loss.