A reason for this setup step failing is that the "Motion and Fitness" feature may be turned off completely for your device. You may have turned off the "Motion and Fitness" settings all together on your iPhone.
To check if you are having this problem, you will have gone through the SmartRhythm/Watch setup flow from the Kardia phone app, but will be taken to the app settings screen to toggle on "Motion and Fitness" but will find that there is no toggle present.
If Fitness tracking is turned off, then the Kardia App will be unable to pull in this information, and you will not be able to complete the setup process.
In order to resolve this:
- Open your phones settings app
- go to Privacy>Motion and Fitness.
- Turn on the first toggle for "Fitness Tracking".
- Return to the Kardia App and force quit it. (https://support.apple.com/en-us/HT201330)
- Re-open the Kardia app
- Re-attempt the watch setup from the SmartRhythm card
You should now be able to fully complete the setup, with the Fitness Tracking activated.