Why does widget glance view never update?

I try to add a glance view in the WebRequest SDK sample.

I want to display the received data in the glance view.

The glance view is showing up but the message string in the view is never updated.

But the System.println("message: "+_message); in the onReceive function does print the correct message.

I have tried it with multiple devices in the simulator but somehow it displays always the initial "123" message string.

I have read that the device needs to have liveUpdates true like the fenix6pro.

But it does also not work in the fenix6pro simulator.

Can someone tell me what I do wrong?

WidgetGlanceView.mc:
using Toybox.WatchUi as Ui;
using Toybox.Graphics as Gfx;

(:glance)
class WidgetGlanceView extends Ui.GlanceView {
  hidden var _message as String = "123";
	
    function initialize() {
      WatchUi.GlanceView.initialize();
    }
    
    function onUpdate(dc) {
    	 dc.setColor(Graphics.COLOR_WHITE, Graphics.COLOR_BLACK);
        dc.clear();
        dc.drawText(dc.getWidth() / 2, dc.getHeight() / 2, Graphics.FONT_MEDIUM, _message, Graphics.TEXT_JUSTIFY_CENTER | Graphics.TEXT_JUSTIFY_VCENTER);
    	 //dc.drawRectangle(0, 0, dc.getWidth(), dc.getHeight());
    }

    //! Show the result or status of the web request
    //! @param args Data from the web request, or error message
    public function onReceive(args as Dictionary or String or Null) as Void {
      System.println("onReceiveGlanceView");
      System.println("args "+args);
        if (args instanceof String) {
            _message = args;
            System.println("args1 "+args);
        } else if (args instanceof Dictionary) {
            // Print the arguments duplicated and returned by jsonplaceholder.typicode.com
            var keys = args.keys();
            System.println("args2 "+args);
            for (var i = 0; i < keys.size(); i++) {
                //_message += Lang.format("$1$: $2$\n", [keys[i], args[keys[i]]]);
                _message += Lang.format("$1$: $2$", [keys[i], args[keys[i]]]);
            }
        }
        System.println("message: "+_message);
        Ui.requestUpdate();
    }
}
WebRequestApp.mc:
//
// Copyright 2015-2021 by Garmin Ltd. or its subsidiaries.
// Subject to Garmin SDK License Agreement and Wearables
// Application Developer Agreement.
//

import Toybox.Application;
import Toybox.Lang;
import Toybox.WatchUi;

//! This app demonstrates how to make web requests through GCM.
class WebRequestApp extends Application.AppBase {

    //! Constructor
    public function initialize() {
        AppBase.initialize();
    }

    //! Handle app startup
    //! @param state Startup arguments
    public function onStart(state as Dictionary?) as Void {
    }

    //! Handle app shutdown
    //! @param state Shutdown arguments
    public function onStop(state as Dictionary?) as Void {
    }    

    (:glance)
    function getGlanceView() {
        var view = new $.WidgetGlanceView();
        var delegate = new $.WebRequestDelegate(view.method(:onReceive));
        return [ new WidgetGlanceView() ];
    }
    
    //! Return the initial view for the app
    //! @return Array Pair [View, Delegate]
    public function getInitialView() as Array<Views or InputDelegates>? {
        var view = new $.WebRequestView();
        var delegate = new $.WebRequestDelegate(view.method(:onReceive));
        return [view, delegate] as Array<Views or InputDelegates>;
    }
}