Air Deccan — no refund processed

Address:

421201

Air deccan flight was cancelled on 27th september 2018. It's 5th november today and they still have not processed my refund. I tried contacting airlines for help, but no response to my emails as well as calls. I am really worried now if they are going to process the refund or not.
I tried to contact airlines several times, initially they said it will take 10 working days to process as their system is down. But even after 15 working days it was not processed. And since then they are not even picking up my phone calls and neither they are replying to my emails.
I feel i might have to take some legal action now.