Graphics not displaying in esri scene

Question

I am trying to build an AR app for navigation, and i am trying to modify the app for rest points, so I decided to add 3d graphics overlay in esri maps while building the app in visual studio, but the problem is I can see a 2d point but when I try to implement a 3d point on a scene it doesn't show up in the map or scene , i tried creating the app in windows, android and iOS but there was no solution and i kept on trying adding layers they are working fine, but every time I am using simple marker scene symbol it's not working at all, not even basic points are reflecting in the map/scene

So this is the developer documentation tutorial on how to create a graphic on a scene: https://developers.arcgis.com/net/scenes-3d/add-graphics-to-a-scene-view/

This is my code that I have written exactly to avoid any mistakes in generation of graphics:

var go = new GraphicsOverlay(); var pierPoint = new MapPoint(xx.xxxx, xx. xxxxxx,SpatialReferences.Wgs84);

            // Create a new symbol for the graphic.
            var redSphereSymbol = new SimpleMarkerSceneSymbol(SimpleMarkerSceneSymbolStyle.Sphere,
                                                              System.Drawing.Color.Red,
                                                              500, 500, 500,
                                                              SceneSymbolAnchorPosition.Center);

            // Create a new graphic.
            var santaMonicaPierGraphic = new Graphic(pierPoint, redSphereSymbol);

            // Add attribute values (if needed).
            santaMonicaPierGraphic.Attributes.Add("Name", "Santa Monica Pier");
            santaMonicaPierGraphic.Attributes.Add("type", "pier");

            // Add the graphic to the graphics overlay's graphics collection.
            go.Graphics.Add(santaMonicaPierGraphic);

            // Add the graphic overlay to the geo view's graphics overlay collection.
            arSceneView.GraphicsOverlays.Add(go);
            arSceneView.Scene = scene;
            arSceneView.Scene = scene;

The arSceneView is the sceneview class the xx.xxxxx is the latitude/longitude for the reference point