I have found by the process of elimination that a child who is 3 or younger (i.e., born in 2020 or later) does not show up on the screen for Elementary and Secondary School Expenses. Is it possible that you mis-entered the second child birth date in the Personal Info?
Note I have gone though the Louisiana Instructions and don't see a particular age limit. But the instructions do say "a deduction for expenses paid for a ... public elementary or secondary school." Is it possible that the state has rules that 3 year-olds can't attend public school?
So how old is the second child?