My HR is display without problems in Golden Cheetah but when I export the fit file it misses a lot of it.
Any ideas?
I opened the fit file for that ride in https://www.fitfileviewer.com and most of the HR data is 152 bpm as shown on the chart.
How did you create the file?
Intervals.icu can process multisport files. You get one activity per sport.
Garmin FR 920xt
When it failed to import properly from Strava, I deleted it and then imported it to Golden C by usb - only the bike and run.
Then I checked to see if they were ok and expoted to .fit.
Finally I imported them to intervals.
So was the original file from the device not a .fit file? (gpx maybe?).