Does anyone know what to do yes it says you’re not eligible for the child tax credit the extra amount even though I absolutely qualify

I filed my 2020 tax return I claimed my two children who are both under 17 I have lived in the United States my entire life and I make way under the income limit and it says that I am not eligible and I don’t know what to do because anytime you call the IRS number they cannot give you any information except for what’s on the site