Hello Winston,
Can you verify that you have Navigator version 2.0 installed? In Navigator, go to Settings --> About Navigator, and you should see the App Version 2.0.0. If this is not the case then you will need to update the app.
Also, the .mmpk file that you created in Pro (version 1.2 or later) must have a basemap, transportation network, and geocoding locator within it.
Tutorials for creating custom navigation maps are here: Prepare maps—Navigator for ArcGIS | ArcGIS
Does this help?
-scott