A minimum of three noncoincident points with variation in both X and Y are required to create ellipse geometry. For an ellipsoid, variation in Z is also required. For some of the Case Field values, the ellipse or ellipsoid geometry could not be created.
Check the features associated with each case value to ensure each case has at least three noncoincident features with variation in X and Y (and Z, if applicable). You can also remove cases with too few features or ignore this message, but recognize that not every case value will result in an output ellipse or ellipsoid.