Have you changed the content of your site and Facebook is still showing the old content when you share the page?
You can get them to update their info by going to the Debugger Page!
Please note if you are sharing a URL that has Masking on it will give a blank Facebook thumbnail
To change this:
- remove the masking on the url at your domain host
- request a “Scrape Again” at the Facebook Debugger Page
- refresh the share content on the Facebook post