When launching a new website that incorporates URL redirects sometimes Facebook is slow to propagate those changes.
The other social networks and even Google respond really quick but Facebook is Facebook and they don’t really play well with others.
However, since the majority of people who post do so through Facebook it’s a good idea to tell Facebook you modified a link and they need to re-index that URL so it’s displaying the right information.
A good resource is Facebook’s own Object Debugger tool. It will show you how they (FB) sees a site so you can go back and fix if needed.
You plug in your URL and press either “Show existing scrape information” or “Fetch new scrape information”.
The “Show existing scrape information” will show you exactly how Facebook sees you the information your website is displaying.
Pressing the “Fetch new scrape information” forces Facebook to update their records about your website and display the newest information.
But it requires you to have an understanding of what it is Facebook is truly looking for when scraping.
But sometimes even their tool doesn’t work.
So it’s matter of being patient and waiting for FB to take action.
Or in my case because I’m not patient – manipulating the website to trick Facebook into seeing what I want them to see.