The service provider does not support the QNavigationManager type

[DangaTeo]

hello to the whole community Qt Forum,
I would like to manage the navigation within a map; This was done by looking at the "Map Viewer (QML)" example provided in the documentation.
I have a .qml file in which I have defined a target "Navigator", when I try to print Navogator.errorString I get the following error: "The service provider does not support the QNavigationManager type." .
Although I can set and draw the route on the map, then Navigator.route is set correctly, but Navigator.direction is still null, probably due to the error I get.

In practice, the path is drawn, but how can I get the navigation information? What does the error mean?
Thanks in advance :)