For 2023 and beyond, the Iowa deduction type (standard vs itemized) has to match what is taken on the Federal return. In the past, you could take the standard for federal and then itemize for state - this is no longer the case. If you took the standard for Federal on this years return the software is likely ignoring the license plate stuff since you cannot itemize for Iowa. If you itemized on the Federal return, well I don't have an answer other than there may be a software error.
