Need to file my 2020 taxes they were denied because I had to prove that I supported my children and in 2021 I prove that I support my children and my taxes were approved?

My 2021 taxes were approved because I showed that I take care of my children, my 2020 taxes were denied because they said that I needed to show proof that I take care of my children which I did in 2021. can I refile for 2020?