The input hot spot result layers are intersected prior to analysis so that every feature in each result layer can be paired with a single feature of the other result layer. The provided layers did not have at least 20 feature intersections, which is required.
For polygon result layers, verify that there is sufficient overlap in the polygons so that there are at least 20 intersections.
For points, verify that at least 20 points in each result share the same coordinates.
For lines, verify that at least 20 lines from each result cross each other or share multiple vertices.