As from June 23rd, 2015 all Facebook feeds will be deprecated and will stop returning data.
Facebook have released a 90-Day Deprecation Notice to notify all users and developers of this, and that it won’t be replacing it with another RSS/XML-returning endpoint, but use JSON instead.
What does this mean for users of WP RSS Aggregator? Unfortunately, this means that all those using our plugin and add-ons for Facebook feeds will no longer be able to import any content via their current feed source URLs. They will no longer be functional come June 23rd. This is something that is completely out of our team’s control and, regrettably, nothing else can be done about it from our end.