This error message is popping up while trying to Export using Datasmith Exporter for Unreal Engine 5.1 using Revit 2021.
Cannot export the 3D view: An item with the same key has already been added. at Autodesk.Revit.DB.CustomExporter.Export(View view) at DatasmithRevitExporter.DatasmithExportRevitCommand.Execute(ExternalCommandData InCommandData, String& OutCommandMessage, ElementSet OutElements)
Any help how to solve it?