Aircosta — refund not initiated for over 8 months

I have booked my tickets with pnr:02spv6 early this year and airlines have automatically cancelled without giving a reason and the refund due is 18, 193.
Its a huge amount and they used to reply that it will be done in 7 to 8 business days and now its over 8 months.
Now i dont even get to them through phone number or email.
[protected]@aircosta.in
[protected]
Kindly take an action on them.