Have you ever clicked on links from your blog share o Send to di Facebook and unable to preview the text or title or image of your article? it happened to me a few times and I've always solved it like this.
Go in Facebook Developers in the debugger page and in the text with the title Input URL, Access Token, or Open Graph Action ID, type the link that you have difficulty sharing from your Blog, click on the button Debug and in the page that opens you will notice the causes that had generated the sharing error, but also the preview of your article with photo, title and link.
After doing this, go back to your Blog and share again and you will see that everything will work perfectly.
Let me know if you have solved it.