Getting the message "This content is blocked. Contact the site owner to fix the issue"

I’ve just started using Directus and created a new CMS template project on Directus Cloud. When using the visual editor I just see a blank screen with the error:
‘This content is blocked. Contact the site owner to fix the issue.’
Same is true if I try to preview any of the pages.

I was able to access the cloud demo project on the Directus website without seeing this error.

Any idea what might be causing this?