Just purchased Fenix 5 plus and since having it the Heart rate stops detecting on and off throughout the day and night. When I reboot it seems to be better for a few hours but gradually gets worse. During activities have not had drop outs. Seems very random as it can go all night without dropping out. Pretty sure I'm wearing it correctly as I've upgraded from Vivoactive 3 which had no problems. I believe it's a software problem but can't find anybody else having the same problems. Heart rate sensor is set to auto. Any suggestions would be appreciated...maybe a widget conflict?