Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
That sounds to me like a Garmin device that needs either or both of the following:
1: to have its battery replaced, possibly
but first, to be tried, is:
2: to be connected to a computer running Garmin Express, and have Garmin Express try to do an update on it. Which sometimes cures such problems altogether without need of servicing or replacement of parts.
When dealing with an update for your Garmin device, it is best to simply download, install, and use Garmin Express.
and (if you have a Windows PC) click on the big blue Download button at center bottom of the page. (If you have an Apple, click on the nearby Download for Mac link.) And download Garmin Express' installer to your computer, save it, then double-click upon it to install Garmin Express.
Then start the program, Garmin Express. Then connect your Garmin device. Then use Garmin Express to update your device.