First, make sure you're updating the year that the refund is for when you enter the refund amount. See screenshot.

Then, you'll need to manually calculate the taxable portion of the refund (if any) for each year prior to 2023 using the State and Local Tax Refund Worksheet. The worksheets are located in the instructions for the 1040 for the next respective tax year. For example, the worksheet to determine how much of your 2022 tax refund is taxable can be found in the 2023 instructions.
