Article not visible to non-authenticated users in Salesforce Community

We have a community build with the KOA template. Most all articles that are set to the data category are visible when searching and when going directly to the URL. However, there’s one article that returns “Invalid Page” error and is not searchable if the user is not logged in.

The “Customer Channel” checkbox is checked on that article. The Data Category is visible to the profile and other articles in the data category do show.

What more do I need to do in order to get the article to show on the community?