I've had instances where the navigation text stops working, and usually a factory reset cures it for me. If you do a reset, switch to the Recreation profile first, then shut it down. When you restart it, hold your finger on the screen in the top left until you're asked if you want to reset. Choose Yes, then let it go. You won't lose any tracks, maps or waypoints, though some of your customisation may need to be redone. Generally a reset is nothing to worry about. Are you using the Nuvi Dashboard? This is what you should expect with that display.