GoAir — Flight Cancelled without Notice, No Refund, No Response

PNR : TDDLYN
Flight : G8 - 345

My flight for 7th June from Kochi to Delhi was cancelled without any prior notice from the airline . I realised that the flight got cancelled only while trying to do the web check-in . They only sent an email about cancellation on 7th June, ie, on the exact Date of Travel (screenshot of the email is attached).
They only provided an option to change the booking to a later date.
Since I work in the Army and had to report on the scheduled day, I had no choice left but to book another flight at a much higher fare, as it was a last minute booking. As there was no option to request refund from their website, I desperately tried to contact Go Air customer service, but customer support seems virtually non-existent.
As a last resort, I sent a mail to the email id given on the website, requesting refund. I have only received an automated reply with an SR Number G[protected]. It's been one week, there has been no reply from them yet. I tried contacting the customer support multiple times, but to no avail.
How could an Airline so irresponsible and unprofessional be allowed to operate in our country? From the many negative reviews I read, I understand that such Last minute cancellations are unresponsive customer support are nothing new to Go Air. I really wish I knew how pathetic their service is before booking a ticket with them.
I cannot keep on following up about this refund for ever I need a resolution from Go Air at the earliest. Flight was cancelled from your end, that too without notice, thereby leaving many passengers in distress. So, at least show the courtesy to refund the amount rather than holding on to refunds and again wasting the time of people who unfortunately booked flights with you .