Fitness app not working

Soringroll,

Make sure both devices are fully up to date, and if that doesn't help, unpairing the Apple Watch and pairing it again is a helpful troubleshooting step for when your iPhone and Apple Watch are not syncing.

Take care.

Hey Soringroll,

If we understand correctly, the Fitness app on the Apple Watch is not syncing activity to the iPhone.

One thing you can do is to unpair and then pair the Apple Watch and the iPhone again.

Unpair and erase Apple Watch - Apple Support

Please don't hesitate to let us know if you need additional assistance.

Thank you for using Apple Support Communities. Have a good one.