Charge 3 does not accurately track my heartbeat during exercise. During vigorous exercise it still shows slow heartbeat and when tracked manually is nowhere near the same. I slow down and when my heart rate slows, the Fitbit shows it going higher. When I look at overall workout it shows none of the fast heartbeats. I have loosened it, tightened it, moved it up more on my arm and lower. Nothing. Still won't track at high heart rate. Anyone have ideas?
