wiki pages have 404 errors on all wiki page loads

Hi

All my wiki pages are giving 404 errors.

I have the latest WordPress version and the wiki plugin is up to date
Opening wikis in the front end from links and from the dashboard using the "View" option results in 404

I have saved the permalinks and saved the wiki settings but both did not help resolve the issue

http://sageography.myschoolstuff.co.za/geogwiki/grade-10/