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vivofit jr. Device Displays a Triangle on the Screen

A vivofit jr. device that displays a triangle on the screen and is unresponsive to a button push is likely experiencing a low battery condition. Changing the battery should restore functionality. 

You can change the batter by looking at the steps in your owner's manual from this link: vivofit jr. - Replacing the Battery.

You can also watch the video below for instructions: