Exporting 3D views to DGN is not directly supported. Modify the Revit.ini file to enable the export of 3D views to DGN files.
Symptom: After you export a 3D view of the model to an DGN file, the resulting file does not have any geometry. The V8 DGN exporter used by Revit does not support 3D views.
Solution: To successfully export a 3D view to DGN you must edit the Revit.ini file to use a previous version of the exporter:
%APPDATA%\Autodesk\Revit\Autodesk Revit 2022
If the [Export] section does not exist, you can add it to the end of the file, following the example in the next step.
[Export] UseVersion2012DGN=1
If the setting does not exist in the [Export] section, add it. If the [Export] section contains other settings, leave them in place.