When you start the route the Nav V will offer you a list of waypoints, from this list it wants you to select one usually the first
(not the Start) I am assuming your route has a few waypoints plus the start and destination waypoint?
In this case select the first waypoint after the start. I am guessing your selecting the start the device is directing you back because its a waypoint you have to ride over it to then be directed to the next one.
If you select the first waypoint after the start the Nav V ignores the start waypoint and directs you along your route.
Word of warning here don't select the destination if you have multiple waypoints in your route the device will take you to the destination as it sees fit calculation mode i.e. faster time and will completely ignore your route
Now If your route is built from shaping points with only two waypoints a start and finish select the destination/finish and you will be guided along your route.
Make sure you are quite near the start of the route over 500 mtrs away from it and it will ignore your route and take you to the destination its own way.
Or use the skip function to skip the waypoint then you should get directed along your route.