Spice Jet Airlines — Refund

I have cancelled the following 3 PNRs on 29/3/21.
PNRs LC2RNJ, BCSTNT, AEJ9YA
Since I am not a passenger, I got the written authorisation letters from the passengers and submitted it on 17/4 and again on 28/4/21.(I have submitted the documents since I only booked the tickets)
I was informed that that documents are in order. So far I have sent more than 10 mails and also contacted customer care center nearly 15 times. Every time I am getting a sterio type letter from the nodal officer that my concern is under active consideration. So far I am not getting my refund. Please suggest further course of action