navigation indicates "unmapped area" frequently

On the day I took possession of the vehicle from the dealer in Kelowna BC to drive to Vernon BC we drove beside the highway most of the way to Vernon according to our navigation system. Highway #97 had been changed the previous year. I was annoyed but was expecting software update on my next visit to the dealer. We have owned this vehicle for over one year and have frequently encountered the message "Unmapped Area" in places like the center of Billings Montana for instance. We have had this same message time after time in old and established areas. We also get "You have arrived at your destination" and after consulting a map we find we are within a few blocks of where we want to go. As a result we have found ourselves lost on many occasions.

We were at the dealership on July 16 of this year and were again told that there is no software update available.

We now carry our Garmin Nuvi as a backup. I would expect a lot more from Mercedes Benz