How to get zones from method UserProfile.getPowerZones()

In SDK 9.1.0 four methods were added to UserProfile: getHeartRateZones2(), getPowerZones(), getFunctionalThresholdPower() and getCurrentSport2().
I can get data from three of them but not from getPowerZones(), it returns null.

I tried it in the simulator and on my Edge 1050.
Did anyone try and succeed?

This is what I coded to test the method:

if (UserProfile has :getPowerZones) {
    System.println("Using getPowerZones from UserProfile");
    var sport = UserProfile.getCurrentSport2();
    var pZones;
    System.println("sport: " + sport);
    if (sport != null && sport.size() > 0) {
        System.println("Using getPowerZones for sport: " + sport[0]);
        pZones = UserProfile.getPowerZones(sport[0]);
        System.println("pZones1: " + pZones);
    }
}