Font Sizes Richtext

Scripting
1

Hello I have a urgent topic.
The TextSize is somehow not adaptable by Richtext Formating. Any Examples or hints?

public static void ReadRichText(GeometryBase Input)
{ 
   var en =(AnnotationBase)Input;
   var r= en.GetObjRef();
    en = (AnnotationBase)en.Duplicate();
    en.RichText.Show();
    // throw new Exception();
     var ax = "{\\rtf1\\deff0{\\fonttbl{\\f0 Arial;}}\\deff1{\\fonttbl{\\f1 Simplex;}}\\f0 \\fs12{\\f0 A}\\fs20{\\f1 B\\par}}";
   // var test = TextEntity.CreateWithRichText(ax, en.Plane, doc.DimStyles.Current, false, 100, 0.0);
   // doc.Objects.AddText(test);
    var box = en.GetBoundingBox(true);
    new Box(box).Y.Length.ToString().Show();
    en.RichText = ax;//.Show();
  
    if (en.GetType() == typeof(TextEntity)) { doc.Objects.AddText((TextEntity)en); doc.Objects.Delete(r.ObjectId, true); }
    if (en.GetType() == typeof(Leader)) { doc.Objects.AddLeader((Leader)en); doc.Objects.Delete(r.ObjectId, true); }

    doc.Views.Redraw();
}