The stretch goal currently supports data captured from the Apple Health, Google Fit apps only.
Some things to note:
To sync your daily goal activity:
Apple watch: Select "Cooldown" or "Flexibility" on your watch
To check your activity data in the wearable device app
Apple Health:
Open the Apple Health app
Under “Flexibility”, check that the stretch data from your Apple Watch has been synced with the Apple Health app.
Google Fit:
Open the Google Fit app
Under “Calisthenics”, check that data from your wearable device has been synced with the app.
If you’re having any synchronisation issues, please visit the device’s official website for more details.