By default, PassagePoint requires at lest parts of a firstname and lastname to search.

To enable searching a Host via intellihint by last name only, change the "requireFirstNameForIntellihints" to True

Home > configure > Screen policy > select the screen you want to change this one (chis one is the rapid registration), Select RequireFirstNameForIntellihit > select True > Make sure you hit your Return Key on your keyboard then hit save

See below screenshot: