A LandCrvPoint does not have a related PointOnSurfByTwoCoords_AE.
A landing curve point does not have a related point on surface by the two coordinates active entity (AE): Missing the PointOnSurface relationship to PointOnSurfByTwoCoords_AE for CLandCrvPoint.
What You Should Do
Ask your database administrator to back up the model.
Supply all information possible that may have led to this situation, and submit this information along with the backup to Smart 3D Support.
Delete the object using one of the following methods:
Select the object in the Workspace Explorer, and delete it.
Run the Clean Database custom command to delete the object.