MB Relationships only displaying partial list of posts to connect

Hello, I’m using Version 1.7.0 of MB Relationships. Here is the code I’m using in my functions file.

add_action( 'mb_relationships_init', function() {
    MB_Relationships_API::register( array(
        'id'   => 'occupant_to_building',
        'from' => 'occupant',
        'to'   => 'building',
    ) );
} );

For some reason I’m only seeing a partial list of occupants from a building post and I’m only seeing a partial list of buildings from an Occupants post. I’m getting a “no results found” notice when I search for an occupant that I know exists in that post type. Any help would be greatly appreciated. Thanks