The vehicle types of your system can be active in one, two, or all of your zones. This setting can be managed in the admin center.
Admin center → Settings → Operation Setup → Vehicle types → Action(Edit)
If you want to choose the zones in which you want this vehicle type to be available (active) so the drivers with this vehicle type can accept orders, you have to unmark the “all” checkmark and add the zone(s) you want separately, as shown in the image below:
Then click on “Submit” to save the applied changes.