New filter creates duplicate pages

Hi,

In Perch Runway, when I click the "New" filter on the "Pages" > "Add/Edit" page I end up with duplicate "Home page" and "Errors" > "404" pages.

Each time I click "New" it creates extra duplicates.

Wondered if this is a bug or something I've configured incorrectly? I have edited the Home page and 404 templates.

Thanks,

Rob