I try to do a 30 min running on treadmill, but the heart rate shows N/A...i have turn on the wrist heart rate... May I know what is going wrong
Try if you find the answer in this support document: The Heart Rate Sensor on My Watch Is Not Accurate
If it does not help, contact the support.
Try many ways, but still unable to detect the heart rate. When go to Health Stats... The icon shows " ---"
Contact the support