@Sarah_Halley’s response is correct.
This automated message is displayed when we detect a free account sharing a doc. If you are encountering this message, you may write directly to support@coda.io with a link to your doc that you’re attempting to share. Our team will review and lift this limitation once we verify your published doc is safe. You won’t have to do this for every doc, but it’s just a safety check to ensure that sharing is not abused.
That said, the feedback to clean up this wording to be clearer has been sent to the team. Thanks!