I recommend connecting it with the USB cable to a computer, recharging it fully, then (if you did not do it yet) install Garmin Express and registered the same (!) account as you use in Garmin Connect. Then check for firmware updates with Garmin Express. When the update is completed, soft-rest the watch (!) (press the Light button till the watch shuts down, then restart). If it does not help, contact the vendor, or directly Garmin and ask a replacement watch.
