Missing preview image when sharing blog post to Facebook
10. Go to the Facebook Debug tool
11. Write your post URL and click Debug
If the error still appears, click on ''Scrape Again'' till will disappear.
12. Go back to your Facebook page and refresh it. See if the error still appears, but shouldn't.
In case if you have more errors like this one you should Debug each post URL without doing anymore the first part of the training (App ID).
I hope this training has been helpful to you.
All the best!