Air India — preponing of flight ai 639 without prior notice

Address:

Mumbai City, Maharashtra

I had book 2 tickets by ai 639 flight dt 21.02.19 which was scheduled at 10.40 am from mumbai to bangalore. The flight was preponed by air india without prior intimation. The intimation was sent on my mobile only 3 hrs before departs. Since i was on the way to airport i couldn't see the information. I was at gate at 10.00 am but by that time flight was moved. Company is not ready to refund my amt or doesn't adjust in next flight. Prior intimation before 12 hrs must be provided.