In 2018 my wife used her personal car for consulting work. In 2019 she did not use it for work, but we kept the car, why will this not show up as an option?

Did you deduct the standard per mile deduction in 2018 or did you depreciate the vehicle?  A lot of times, the program will say "needs review" just so you can look back and see if you put in the correct information in the right place.  If you used the per mile deduction, you don't really need to do anything in 2019 if the car was not used for work.  If she still does the consulting work, you can put your total mileage and show "0" as your business mileage.