Heart Rate Data not showing in activity app
I have had to reset both my iPhone and Watch Series 2 recently and for the first few workouts heart rate data showed perfectly in Health and Activity App's. For the past three days ( and workouts) I have now noticed that the heart rate data is not being shown in the activity app under the workouts tab. Instead it merely shows 'Data Unavailable'. The heart rate data is shown in the Health app for the workout that I have completed. I have attached a couple of screen shots to show what is now being displayed on the iPhone in the Activity App. Please can someone enlighten me to get this data back into the Activity app??? I have checked all the settings on the Watch, Health and Privacy apps to no avail and I am not wearing it any differently?!
I am running an Apple Watch Series 2 Nike edition (only using the Apple workouts at the mo) on OS4 and an iPhone 7 on iOS11.
Thanks for any help!
Apple Watch Series 2, watchOS 4