Public member directory

I added a member directory. the only fields i want to show are first, last name, email, and firm name. that shows fine. the issue is the search does not work. when entering a first or last name, the directory shows no records found. i am not sure why this is not working properly. the default list also appears alpha by first name but would prefer alpha by last name. here is the linkhttp://cabaonline.com/directory/ any help greatly appreciated

https://wordpress.org/plugins/s2member/