A LandingCurve ActiveEntity does not have a related base curve.
There is no definition of the base curve: Missing the LandCrvBase relationship to WireBody2 for LandCrvIntersect_AE, LandCrvOffset_AE, LandCrvProject_AE, LandCrvTable_AE, LandCrvER_AE.
You cannot manipulate the object itself or other objects related to it.
What You Should Do
Open the model.
In the Molded Forms task, select the object, and modify it, if necessary. Or, select the object, and perform a re-computation to update it.
Re-run the Check Database Integrity custom command and the DBIntegrity report.
If the object is still posted, contact Smart 3D Support.