Hello @Rickmag
Is the heart rate switched on in the settings? From the Clock Face screen scroll down until you get to Settings, tap, then scroll up until you see Heart Rate. Is it switched on? If it's off, tap it to turn it on.
If it's turned on but not reading your heart rate, look at where it is. Do you have a tattoo on that wrist? The Charge 5 sensors seem to have a problem working through tattoos and it would be worth moving it to your other wrist if so.
You can also try restarting your tracker by going to Settings again but then scrolling up to the very end to Restart Device and then following the instructions.
I hope that helps you a bit.
