first did you have a personal tax loss for 2018 - was adjusted gross income negative?
if you did have an nol then did you make an election to carry it forward. if not you must amend 2016 and 2017 if they didn't show an NOL then any remainder form 2017 gets carryforward to 2019
use form 1045 schedule A to determine if you indeed had a 2018 NOL.
