Spice Jet Airlines — Not informing about delay in flight by 6 hours

My grandad was traveling from HYD to MAA on 20th November in flight no. 323. The flight was initially scheduled to depart at 16:35, so we reached there 2 hours before it, but upon reaching he found out at the check-in counter that the flight is delayed by 6 hours. There was no SMS sent to him about the delay or was any information provided in prior.

This kind of miss costs us both time and money, I would like SpiceJet to look into why this happened and also I would want some compensation for the delay for 6 hours which was wasn't even informed.