Select categories not showing content


I am making a movie website, where I have made "films" as custom post types. I have made two categories named "Kommende biograffilm" and "Kommende DVD" (upcoming movies in cinema and on DVD), but they don't display, when I select the two category pages.

See an example of a movie with the category "Kommende biograffilm":

But when I click on the category it is empty:

Do you know what causes this?

Thanks! :o)