Are you comparing against 2019? When I did this for 2020, when comparing to 2019 it shows $0.00 for state and local taxes greater than 10k.. but when I open the 2019 software to view it shows the correct negative number. It didn't load my 2019 into the 2020 software correctly to demonstrate the comparison.. this is just comparing to last year and won't effect your taxes. If you're alarmed you're seeing a negative number, it's because it's capped at 10k. The negative is showing how much over the 10k you weren't able to claim because of the cap.
