Garmin satellite issues

Question

I have a new garmin nuvi 200. Used it today and when I put it in the window mount it would not acquire a satellite- for over 1/2 hour. Then it would get it for a minute and drop it. In frustration I took it down and set in the passenger's seat- poof, it started working and worked fine. When I put it back in the window mount it lost the signal again and again. Any thoughts?