2D Not working with .fbx file

[amruta-k-k]

Hello Team,

I have integrated this code in my app, its working great with sample rvt files.
My client has give me .fbx files which are not working. Getting error here

  var geometryItems3D = Autodesk.Viewing.Document.getSubItemsWithProperties(document.getRootItem(), {
    'type': 'geometry',
    'role': '3d'
  }, true);
  var geometryItems2D = Autodesk.Viewing.Document.getSubItemsWithProperties(document.getRootItem(), {
    'type': 'geometry',
    'role': '2d'
  }, true);

3D is generated, but 2D is not generated