My Xbas is too high. This is my first time I am claiming Self Employment but I have been using my vehicle since 2017 for my work. I own the Vehicle. How do I fix this?

I have no prior claims on my vehicle and I entered all the info from my papers that I have.  My vehicle was bought used.  It says enter excess basis but Idk what that means.  I've check all the boxes and the info is correct for all the boxes.  I don't know how to fix this or what to enter.