I was wearing my Forerunner 255 all the time. It stopped tracking my activities (heart rate, steps etc.) from about 8 a.m. and only resumed at 2 p.m. Upon checking history, it happened before for shorter periods.
Something like this?
It's a new feature (Of course it's a bug!) in 17.26 - The watch does a reboot sporadically and loose not synced data.
It is very odd. The number of steps over that 6 hours show on my watch but not on my phone (Garmin Connect).
Yes, it's like that. Happened for 6 hours. It must be a bug with the latest update. Hope Garmin fixes it soon.