Ohio. I forgot a 1099-INT on my federal. I amended it. In that process, it prompted me for tax paid -- this was a state field, but I thought it was federal. I input the amount I paid federally, instead of the state amount (which was 0). I submitted it. The federal return got processed, but I did not mail in the state return yet. However, when I go to fix the state return to note the fact that I did not actually pay any state tax, it now says I OWE the amount that I already paid in federal in state.