In Maryland, there is a deduction for income from U.S. government obligations (line ab on this form: https://www.marylandtaxes.gov/forms/22_forms/502SU.pdf). Turbotax has always had a place to enter this information but it seems to be missing this year. Why is it missing from turbotax?
Where did you enter it? Was it on a 1099 box 3? If it was it probably is already automatically deducted.
No, it's not found on a 1099 form. It has to be manually calculated using info like this: https://www.vanguard.com/pdf/USGOIN_2023.pdf
So then you enter the result of the manual calculation on MD form 502SU. Usually Turbotax has this as an option, but this year it didn't.
You entered the total dividends, from the Vanguard fund, at the 1099-DIV screen. After doing so, you get a screen titled "Tell us if any of these uncommon situations apply to you". Check the box "A portion of these dividends is US Government interest". The follow up screen is "Enter US Government interest". Enter your manually calculated amount in the box at that screen. That amount will automatically carry to the state return, for the deduction.