If you have a 1099-G showing a state tax refund, you enter it under the 1099-G section for state and local tax refunds. There are several 1099-G sections that report different things.
It is not taxable to you if you did not itemize your expenses in the prior year or if you did itemize but took the sales tax deduction instead of the state income tax deduction. The IRS sends notices to you because they don't bother to check and see whether you itemized or whether you took the sales tax deduction in the prior year. You can send them a copy of the prior year Schedul e or your 1040 to prove your state refund is not taxable income, should they send you a letter.
To enter it, type 1099-g in the Find window on the upper left.
Select the line below that says state and local tax refunds,
then click on the Jump To that appears.