Hi my watch isnt displaying heart rate form the chest strap?its connected apparently?and when i first connected it it displayed a reading on the watch but then just disappears?
Do you mean in the widget or in a DF in an activity? When you start an activity, doing that will try to connect to the band, but it's not normally connected.
When you start an activity, like "run", it will start up GPS and connect to external sensors that have been paired, such as a HRM band. If it connected to an external HRM, OHRM will be turned off. When you end the activity, it will disconnect from external sensors and if GPS was used, turn that off. If it had turned off OHRM, that's turned back on.