You should have listed child 1 as living in your home more than half the year, that you were not releasing a dependent claim, and that child would qualify you for EIC, head of household, and $2000 tax credit.
Then, you should have listed child 2 as living in your home more than half the year, and that you were releasing the dependent claim. Child #2 would qualify you for additional EIC (you already qualified for head of household) and you would have to print form 8332 to give to the other parent.
The other parent must list that the child lived in their home less than half the year and that they have a form 8332. This will allow the other parent to claim the $2000 child tax credit but not qualify for EIC or HOH. The other parent should be able to e-file, and then they mail the signed form 8332 to the IRS with a cover page after their e-filed return is accepted.
You can double check your tax return by going into the program and look at the list of dependents. Child 2 should be listed as something like “not a dependent, use for EIC only“. You can also print your tax return or look at the first page of the PDF and see if child 2 is listed as a dependent.
If you filed according to the instructions above, and the other parent‘s tax return is being rejected, then possibly the other parent is trying to claim the child as a dependent as if the child lived in their home the entire year and allows them to qualify for EIC and HOH in addition to the child tax credit. The other parent must fix their tax return so that they only claim the child for the child tax credit.
Since we cannot see either your tax return or that of the other parent, it is impossible for anyone on this board to tell exactly what is going on.
