Hello,
are you using the manual import function by any chance?
The best way to manually upload workouts from other devices that are not directly connected is to create a rowing/cycling/running (or other) workout, open it and use the Upload .fit file.
Do not use “import data” in settings- that’s for bringing large historical data into the platform in .zip file format
Do not use “attach file” via workout menu (top right three dots) as this will only attach a file and not read it.
We do not currently have NK Link logbook in our roadmap - please request here: About the Feature Requests category
Best, MJ