HappyEasyGo — Covid test mandatory not mentioned in the ticket

Hi,
For my booking from Bangalore to Kolkata
In the ticket it was not mentioned in the guidelines that covid test is mandatory.
Due to their mistake I had to pay RS 6400 for rapid covid test and board the next flight.
In other sites like makemytrip it is mentioned. When asked for refund as it was their carelessness to not inform customer they completely refused it with no proper response from customer care