I reinstalled WP and Duotive-Fortune theme is working fine now.
But I think it must be to do with a plugin within Duotive-Fortune.
Other plugins I had from the list were:
all Duotive-Fortune plugins
WP-PageNavi
Breadcrumb NavXT
Akismet
Hope you find a solution > I’m guessing if you already have a site built, you don’t have the opportunity to completely reinstall WP.