From a T777 (salaried employee given a T2200) or a T2125 for self- employment?
I am unaware of the version of software you are using therefore I will refer to both, the online version as well as the actual form.
You must have entered the vehicle details in the rental section rather than the self employment section.
There is no place in the Rental Property form that I see on my screen that shows the vehicle entries. It is a bug in the system and I have escalated this issue to the President's Office.