Turn by turn navigation

Hello,

I am new to handheld GPS, I recently purchased a Garmin Oregon 650 and loaded a generic routable map of NZ. However it doesnt seem to support turn by turn navigation. When I try to navigate to a POI it just shows a straight line from my location to the destination. Is this a problem with the map itself or my settings?

Thank you in advance.
Pramod

Are your navigation settings correct (direct route gives a straight line)