South Bengal State Transport Corporation [SBSTC] — Didn't get my refund

I booked a ticket on 08/08/2021 from stsbtc online booking, then I decided to cancel the ticket but from their official website I am not able to cancle my ticket once I click the cancel button for cancelling my ticket the webpage doesn't respond accordingly after that I dialed the number which they mentioned on their site ([protected]) but doesn't get any response so I immediately sooth a mail to them I got response after 12 hrs and informed me that "You have to cancel at you own", where their webpage cancel feature is not working, it's beyond my understanding so lodge a complaint against this loot by west bengal govt.