Up until 2 days the device was detecting heart rate fairly accurately during my cardio activity. Now it tells me my heart rate is 96 when I feel my heart bursting out of my chest. It detects I'm mostly in zones 1 and 2 (up to 124bpm) when 3 days ago for a similar activity intensity I was mostly in zone 3 and 4 (125-160bpm). Anybody experience a similar issue? Is there a way to restart the device or reset the heart rate monitor? The device is just past 1-year old (Sept 2018). I don't think an update on the device happened before the issue started that might have caused it. Any suggestion on what to do?