I've been with Garmin 10 years now and never seen this. My running pace graph is a flat line. The attached images is from an outdoor 6k run. I never paused the watch (Forerunner 935) during the run. I've reinstalled the app and the apps up to date.
I've been with Garmin 10 years now and never seen this. My running pace graph is a flat line. The attached images is from an outdoor 6k run. I never paused the watch (Forerunner 935) during the run. I've reinstalled the app and the apps up to date.
The source data for this activity indeed does not contain any pace (speed) values. Speed at all trackpoints is zero. Similarly, the fields "Vertical Speed", "Fractional Cadence", and "Moving Duration" are equal to zero for all trackpoints. I do not know why - one possibility is a corrupted FIT file of the activity, another possibility is a hardware failure of a sensor, or a software problem.
I recommend soft-resetting the watch - sync, then press and hold the Light button for up to ~30s, till the watch shuts down, then wait a few seconds, and restart. No worry, no data and no settings get lost in tis way. Also back up and clean up the folder //GARMIN/Activity/ on the watch. You can also delete all files from the folder //GARMIN/RemoteSW/
When done, do another test activity, and see whether it helped. If not, try the master reset to factory defaults, and if it does not help either, reach out to the Product Support through https://support.garmin.com