Most errors are caused by plugin updates.

Plugins are not the only breaking point in an otherwise smooth sailing WordPress site. Older WordPress themes may cause your site to fail as well

Broken links refer the links on your website that directs or points your visitors to a page or a file that no longer exists

Broken links refer the links on your website that directs or points your visitors to a page or a file that no longer existsWeb performance is the speed in which web pages are downloaded and displayed on the user’s web browser. Web performance optimization about increasing web performance

Broken links refer the links on your website that direct

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There is no particular reason why Facebook shows the incorrect thumbnail image. The most possible reason is that Facebook works with Open Graph(og) label which set the various pictures for the og: picture tag.

OG tags and numerous WordPress plugins like WordPress is utilized by Facebook so it naturally adds the og labels to anticipate the missing thumbnail issue.

Other potential reasons are caching plugins, CDN issues, missing open graph meta tag for the thumbnail picture, and so forth.

There are so many reasons behind this issue so it’s very difficult to find the correct issue. That is the reason you need to go for a couple of strategies to find the right solution to the problem.

Let’s take a look at the methods-

Uploading Thumbnail Image Manually is one of the quickest and easiest methods to fix this issue.

Unfortunately, this strategy doesn’t work for the individuals who want to share your post on Facebook because there is a possibility of showing the wrong thumbnail in their shared post. That is the reason that this is the easiest strategy but this strategy is not reliable.

Using WordPress SEO by Yoast Plugin is another strategy to fix this issue. You need to scroll down the Yoast meta box post editor, after scrolling you will see a social tab on the left side. Click on the tab, then you will see the Facebook image upload button where you have to add the Facebook thumbnail image.

If you are still facing this issue after doing this then you need to reset the Facebook cache.

To reset the Facebook cache, you can utilize the Facebook Debug Tool that investigates issues on your WordPress site with facebook open graph execution. It is on one of the effective and easiest strategies to fix the thumbnail issue.

Utilizing Method:

Open the Debug Tool, you can see the sharing debugger box where you will get the data that is utilized when it is shared on Facebook.

In the next step, copy the URL of the post and paste it on the debugger tool and after that click the “Debug” button.

It will show you the refresh or updated content. The Facebook crawler brings the picture that is utilized as the thumbnail picture in the post.

If the tool shows the below error then,

Provided og: image is not big enough. Please use an image that’s at least 200×200 px. Image ‘http://abc.com/uploads/2018/17/example-image.jpg’; will be used instead.No need to worry, just click on the ‘Debug’ button again the error will disappear itself.

When you log in to WordPress, it sets a browser cookie with which it verifies your login session. If there are any errors with this cookie, for example, a distinction between the URL set in the cookie and the URL with which you are getting to your site, WordPress will be unable to verify your session and will subsequently log you out. As a rule, you will see a message like “your session has expired”.

If all the above steps get failed then this is the last step that can help you to fix this issue. Sometimes, a plugin can cause this issue, you can track the source by disabling your plugins.

Also read, How to Disable WordPress Plugins Using FTP.