Facebook (#10) This message is sent outside of allowed window.
On March 4, 2020, Facebook changed its policy for using the official API to reply to direct messages.
You may now only reply to direct messages on Facebook for 7 days after the last message from the user.
This restriction applies to all third-party apps, there is no restriction if you reply via Facebook directly.
Hence, if you are encountered with this error, you can go from the service to the relevant one in Facebook and post a reply in Facebook directly.
You can read more about the restrictions imposedin Facebook's official documentation.