MfgBevel does not have Geom2D.
A Manufacturing Bevel object does not have a Geom2D.
Coding or data model errors in an earlier version.
What You Should Do
To delete the object, run the Clean Database custom command (ProgID: SP3DCleanDatabaseCmd.CCheckObj). This command displays a dialog box that lists the objects in error. From the list, you can select the objects and delete them.