Philips DL8790 User Manual page 64

Problem
Heart rate signal
is not showing.
64
Possible cause
Strap is not fastened tight
enough around your wrist.
Personal settings are
incorrect in the app.
Watch or skin is not clean.
Solution
Make sure the watch is worn
correctly (see 'Wearing the health
watch'). Indicate the side you are
wearing the watch on in the app.
In the app you can also select if
your wearing side is your dominant
hand.
Update and correct your personal
settings in the app.
Clean the device and your skin
under the device.