Air India — Denied boarding domestic flight due to overbooking and missed international flight

I wanted to travel from Aurangabad to Tokyo and I was denied to board the domestic flight from Aurangabad to Delhi(AI442) on 3rd May, 2022 and due to this I missed my international flight from Delhi to Tokyo (AI 306) too.
I was in the airport at 3:45 pm, one and half hours before the departure of the flight. When I went to the Air India counter to collect the boarding pass, I was told that I had not done web check-in and so had to take the next day flight though I booked the tickets two months before and I also booked the seats by paying extra money and was having seat numbers in hand.

Due to this I suffered a lot as I was traveling with my 2 year old kid. Also as I was traveling internationally, I needed to do lots formalities again during COVID-19 pandemic like doing rt-pcr test etc.