I'm running the free version of Jira Service Manager. I've created a JSM instance using the "customer service management" template. I've linked the project to a Confluence space, and have created several KB articles. I've configured project and customer permissions to be as open as possible, as I want KB articles to be found without requiring logon.
I thought I had it working for anonymous access, but I must have inadvertently changed something, as articles can't be found. Even if I log in with a "service desk customer" account, articles can't be found. When selecting a category, or attempting to access the direct URL for a KB articles, I get the following:

The only thing I remember doing before it stopped working was deleting the pre-built how-to and troubleshooting "templates" (they were showing up in search and I didn't want them to):

So I created a brand new service management project and linked to a brand new confluence space. But those articles don't show up either.
I've not changed any of the project permission scheme settings/permissions.