The selected fitting(s) cannot successfully change the type. The newly selected fabrication part type has a problem with the angle dimension of the current fitting(s), resulting in bad geometry. 
   Namespace:   Autodesk.Revit.DB  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 18.0.0.0 (18.2.0.0) 
Syntax
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