Flight cancelled

I had booked 2 tickets from Delhi to Coimbatore for 12th November few weeks back. I received a message on 11th morning that the flight has been cancelled and was requested to call on a particular number – I tried that number for few hours but to fail that number was not reachable and finally when I got through the number I was requested to change the dates of my booking which was not possible as all other booking had been paid in advance and specially this was a gift to my parents (senior citizens). I told them that as per the message they would have an alternate booking arranged for me but to which I was refused and only given the option of delaying my trip by a day to which also I did not get a guarantee that the flight would not be cancelled. This resulted in me asking for a refund and had to go ahead and book a new ticket for Indigo for rs25,500 whereas the earlier ticket booked was for rs6,100 (approximate numbers). I am asking for that money to be paid along with a penalty of rs 10,000 for troubling us at the last moment. Extra amount paid for re-booking – rs19,400