The message “Sorry, this feature isn’t available right now: An error occurred while processing this request. Please try again later.” is generated by Facebook.
We don’t know exactly when it’s shown and what’s the cause, but it’s not related to the game. From our experience, it appears to show up when shared photos or posts (on your wall or in messenger) are no longer available in the meantime (possibly deleted).
You can tell it’s a Facebook-generated message and not one from CLM because the window has the same blue color like the rest of Facebook, and the company’s “f” logo at the top-left.