An Error occurred while executing an acion

I have a scenario in native mobile application of mendix where we are retrieveing a vehicle that needs to be delivered and displaying the data inside a data view which is placed inside a listview and the datasource of the listview is a nanoflow which return delivery list and the datasource of dataview is also a nanoflow which return the object of associated vehicle. The data is getting populated in  i.e Vehicle that needs to be delivered is displayed on the screen.  There is a button below to start the delivery though the details of the vehicle is getting populated we are facing the error that unable to get a member from empty variable $Vehicle. Attaching the error picture for reference Any suggestion on how to fix this 
1 answers

Apparently the variable $Vehicle is not containing a object of Vehicle.

This can be caused by several things;

  1. Security issue, user hasn't access to the object
  2. Retrieve does not return an object
  3. The object doesn't exist at all
  4. in case of native; the object is not available offline

Your question doesn't describe the expected origination of the object, thus hard to answer more detailed