Nuvi 52 unable to install Garmin map updates

I decided yesterday to update my maps. Mistakenly, I had not done this task timely. Due to some technical faults, or somehow, my detailed Garmin maps were lost and now I am unable to update my Garmin maps. When I started, Nuvi had disconnected and shut off immediately. The USB ports are not shutting off and have enough power potential. What should I do for Garmin GPS update for my device? This question is making me more disappointed, so guys share your ideas for clearing this doubtful question for me.