How to remove a 3D item Model3DGroup?

Hi all. There is such a layout:
<modelvisual3d x:name="Model3D">
 <model3dgroup x:name="Group">
 <ambientlight color="DarkCyan">
 <apart color="White" direction="-5,-8,-7">

Add new 3D elements: Group.Children.Add()
Trying to remove this: Group.Children.Clear()
All removed, but then can not add new elements. Why?
Tried wrapping in a try/catch, but nothing caught
June 10th 19 at 16:52
1 answer
June 10th 19 at 16:54
Try after Clear() to make
Group.Children.Add(new ModelVisual3D() { Content = new AmbientLight(Colors.White) });

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Ran across this answer. Did not help me. I don't remember exactly what it was, but it was the kind of error with data types

At home tonight I'll try again and write. Thanks for the answer - heloise13 commented on June 10th 19 at 16:57
Cannot convert from "System.Windows.Media.Media3D.ModelVisual3D to System.Windows.Media.Media3D.Model3D"

As said - heloise13 commented on June 10th 19 at 17:00

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