Hi everyone! Don't you know what it could be???
When I play ice hockey (in pictures), I don't have my watch (F7X Pro SS) on my hand, it stays in changing room.
As you can see, the start of activity is in changing room (watch has signal to HRM, so there's short heart rate recording, than I go to ice ring, when I come back to changing room the signal is restored and there's short HR recording again till I turn off the activity...)
The interesting thing is that I can see chart for HR in general dashboard, but not for activity itself.
In my whole other activities (running, cardio, weight lifting...) it's ok, but in these activities I have my watch on my hand.
This problem appeared after the update to v18.14, so maybe that's the problem.
Many activities of ice hockey were fine before this update with my watch in changing room...
Now I updated to 18.16, so I'll see in my next match in 2 days.