Pagination problem - clicking page 2 shows same ads

I am using the WP-PageNavi plugin to paginate my classifieds until pagination is added to the Classifieds plugin. I had my Classifieds site set up so the "Front page displays" setting in Settings>Reading (wordpress 3.3.1) was set to "A static page" and Front Page was set to the Main Classifieds page.

The problem I ran into is that when set up that way the pagination was not working correctly. When I would click the link to go to page 2 of the classifieds it would show me the same ads that were on page 1.

How can I fix this?