If there's Sensus connect installed in your vehicle and you are able to see this message once having pushed the NAV button or it simply appears in VDASH, it means that your vehicle has a navigation map for certain regions or countries in places such as Europe or the USA. This allows you to activate the navigation in your vehicle, with lifetime free map updates.
If you can see this message:
Or have this button:
Then all you have to do is simply activate the navigation using this menu in VDASH:
After you have done this, you need to lock your vehicle for 5 minutes minimum.
Sometimes you also need to change the region of the vehicle in order for it to accept the new map data, which is shown and explained at the end of this article: https://d5t5.com/wiki/vdash/article-volvo-engineering-mode-change-region
Once you have done that, you can download map updates from here: https://www.volvocars.com/uk/support/downloads/maps/mca