You received a Form 1099 (with NO prefix or suffix), generally limited to interest paid *by* the IRS on delayed tax refunds; that interest is taxable by both the IRS and your state. (Though paid by the Federal government, it is NOT exempt from state taxation because it's not from a Treasury security, U.S. Savings Bond, or other government security.) Since it's essentially the same as a 1099-INT issued by private payers, enter it in TurboTax as a 1099-INT in the interest section.
You received a Form 1099 (with NO prefix or suffix), generally limited to interest paid *by* the IRS on delayed tax refunds; that interest is taxable by both the IRS and your state. (Though paid by the Federal government, it is NOT exempt from state taxation because it's not from a Treasury security, U.S. Savings Bond, or other government security.) Since it's essentially the same as a 1099-INT issued by private payers, enter it in TurboTax as a 1099-INT in the interest section.
Turbotax calculated an increase in my federal tax for 2019 when I reported the interest income that I received from the IRS on an overpayment of federal tax from a previous year; however, this is in effect a refund of the interest previously charged to me when I was forced (due to an IRS error) to make the overpayment. Shouldn't I be able to avoid paying tax on this interest, since I did not previously receive a tax credit for the interest expense I was (over)charged on the previous tax overpayment? If so, how do I make the adjustment on my 2019 return?