Jet Airways — Refund not received even after 3 yrs for flight that was Cancelled by Airline

Address:

Nallasopara east, Dist Palghar.

I had booked JET AIRWAYS flight from Varanasi to Mumbai for my wife, child and Sister in law for dated 27 JUN 19 14:05 ( Varanasi Mumbai 9W3530 )
The PNR number is HWHEVU.
The flight was cancelled by Airline before day of flight.

The booking was done via GOibibo. I have contacted so many times to GOibibo but they are saying that the resolution is in progress.

Still after 3 yrs is am not getting my money back