I used it on a run and it tracked my heart rate just fine. When I got home the screen was black and wouldn't turn on. The battery was fully charged when I started my run. I connected to the charger and it did not vibrate. I cleaned the sensors on the watch and the charger to ensure connectivity. I then connected the charger, hit the button three times and waited ten seconds. No response at all. It has been working great without issues until the update. I would like to get this fixed out a replacement as soon as possible. Monitoring my heart rate is very important for me. Thank you.
