I wanted to update the link image that Facebook uses for one of my websites (TWSS.tv) which runs WordPress, and it sent me down a rabbit hole.
Here’s what I did to force Facebook to update that pesky thumbnail:
• Turn off my caching plug-in (for me it was WP Super Cache)
• Added a featured image to my sticky post on the front page (an option when editing the post if your theme supports it)
• Added and enabled the plug-in OG (this step was necessary for me to override the default Jetpack image which I couldn’t figure out how to refresh)
• Went to the Facebook developer’s site (https://developers.facebook.com/tools/debug/sharing/), debugged, and refreshed the image
• Reenabled the caching plug-in
• Success!
Hope this helps someone 🙂