Could you please double check your Facebook settings > Apps > Royal Story > 1. App visibility and post audience: "Public". 2. "Post" option is on?

At the same time, please also check your "activity log". They may be stuck there. If so, please allow them showing on your timeline.

If you have ever hidden posts from Royal Story before, please also try the following:
  1. Visit a Facebook friend's profile who plays Royal Story and pick any of the available Royal Story posts.
  2. Click the arrow down button on the right side of the post and choose "I don't like this post".
    3. Click on the option "It's annoying or not interesting", then "Continue".
    4. A notification that "you will no longer see posts from Royal Story will appear". Click "Undo" then "Done" and this should be fixed. :)