Garmin Connect not reporting HRV Status

I've had HRV enabled on my Fenix 6 for over a month and when I go to either the HRV Status or HRV Stress reports on the Garmin Connect website or the Performance Stats > HRV Stress on the Android app I get a "You have no data for this time period." and "No data available" message.

However when I go to Performance Stats > Training Status I get the message "Your training load is optimal, but your HRV status indicated accumulated fatigue." (I have a cold at the moment) so the watch is recording HRV data. Has anyone else come across this?