The Garmin Connect mobile app and website always show 0 seconds in Zone 7 (Neuromuscular) for every workout.
Here's the same data in Strava:
I see this was reported 2yrs ago on here and nothing happened. The suggested solution of changing the Zone 7 upper limit is not correct as Zone 7 doesn't have an upper limit on my device (1030 plus), it is simply set to > 150% FTP.
I have reported the bug to Garmin again.