No Voice guidance available for your area
 

My Bose factory navigation system will not give me directions anymore. It is probably operator error but it used to give me directions to different destinations but now when I try to enter a previously used destination it gives me a message of "no voice guidance available for your area." Can someone tell me what I am doing wrong? I would greatly appreciate it. I feel stupid asking for directions when I have such an advanced navigation system installed in my 2002 Deville DTS from the factory. Again thanks in advance for any help.