Air India Make My Trip - Refund on flight ticket by AIR INDIA as they didn t inform passengers on new COVID protocol and deni

I had booked my flight from Delhi to Mumbai on **th May **** - flight no. AI **** and had web checked in the flight ** hrs prior.
To my surprise i was denied boarding as I didn't have RT PCR COVID negative test results in hand. Firstly this change in policy of having covid RTPCR test before boarding a flight was not informed neither by Air India nor by Make my trip and instead an email was sent asking for passenger declaration of covid symptoms experienced if any.
Every passenger has right for information and this change of covid policy was not informed to me and many ( ** to ** passengers) other passenger like me traveling from Delhi to Mumbai and other destinations.
Air India cannot deny boarding after web check in, Air India should have asked its passenger to have RT PCR TESTING done prior to web checked-in or some pop up reminders to inform them of new covid protocols. This is complete cheating by AIR INDIA and make myvtrip where consumers are not informed and made to have lost their money plus physical and mental harassment for no mistake of theirs. Either refund must be given or such passenger must be at least be given next flight ticket and denial of both is a torture for passengers like me.