Air India Ease My Trip - Air India denied boarding

Hello Air India,
I travelled from Paris to Chennai through Delhi. The booking code is NKB*LY. The flight number is AI *** from Paris to Delhi and AI *** from Delhi to Chennai. The flight left from Paris at **:** and reached Delhi at *:** which was late by ** minutes and given the transfer time being reduced considerably from (*hr **mins to *hr **mins (due to the delay)). When I exited the flight to catch my connecting flight, the air India authorities caught few people at random for, 'Covid tests' which wasn't specified any where before and I was charged *** rupees for that which was okay. But, due to this, another ** minutes were WASTED. I needed to go through immigration, collect my baggage, go through customs check, check in again and clear the security for my connecting flight in ** minutes. But, after I completed my immigration, it was already *:** and I saw so many people still waiting to collect their baggage. Due to this delay, the people who had connecting flights to various locations such as Chennai, Hyderabad, Bangalore etc. missed the flight. But, then we were informed by the Air India authorities who themselves were late to the location that we will be getting boarding passes to the next flight which is not acceptable, totally unforgivable. On top of it, we were made to stand for an hour without any food, no prior communication about the scheduled time of next flight. WE WERE PROMISED BY YOUR AUTHORITIES THAT WE WILL BE PROVIDED WITH A DELAY CERTIFICATE, A MEAL PASS, VOUCHER.
There were total of ** people including me who missed their connecting flight to Chennai due to YOUR mistake. We were informed by your authorities that our next flight will be at **:** and that we will be give boarding passes by **:** PM. The time was **:**PM and still no boarding passes were issued and when we asked the authorities what was the reason for delay, they kept answering it will be ready in * minutes but this drama went on till **:** (the flight time being **:**) and finally our boarding passes were given. But, already the place was so crowded and this should have been well planned so that we would taken that flight without any hassle. But there were fights between the airport security and your authorities because of all this drama. But, finally, we checked in. When we reached the security, the time was already **:** and there was too much crowd and we were in so much hurry to clear the security. FOR YOUR INFORMATION, THERE WERE SO MANY OLDER AND ELDER PEOPLE ALONG WITH US AND EVERYONE NEEDED TO GO THROUGH THIS. When we cleared the security, the time was already *:**, we needed to rush to the gate given the time constraints which was so far from the security.
We didn't anything we were promised and besides that myself including all the other ** people are not going to book our flights through AIR INDIA EVER AGAIN!
We didn't expect this from AIR INDIA. It was so poor and the situation was mishandled, your representative were so arrogant and all of them didn't speak English! Due to this, we had so many plans which we needed to do on Saturday but everything got messed up due to this!