Air India — Wrong information from Air India customer care or Air India station master Amritsar

Hello,

I booked and insured my travel on 2/11/20 from Amritsar to Mumbai for 21/11/20 using easemytrip website. I got confirmation from easemytrip regarding booking confirmation on same day.
On 11/11/20, I got sms from Air India flight is rescheduled.
On 20/11/20 evening, 21/11/20 morning and evening I tried unsuccessful attempt to web checkin. I was getting error message from website.
I called Air India call center regarding the issue I was facing. Air India agent told me your flight is cancelled, due to which you are not able to do web checkin. I was not informed neither via mail nor sms or call.
I approached ICICI lombard for insurance, they requested me for the certificate for cancellation of the flight.
When I approached Air India customer, they told they are not authorized to provide the certificate.
Then I approached Air India station master Amritsar. I got communication flight took off on 21/11/20