MonasteryTech

Why dont you try changing the themes. Tell what is your site about may be i can recommend a better one
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Your wordpress install is not connected to the wordpress server. Try configuring the config files again and connect to the database again. Once connected go to settings and set the time and date of your installation. This might be server time and date clash

OR

You can do a fresh install of the wordpress development site on local host and that means installing WAMP again you can follow this tutorial as well to set it up correctly

Did you recently uploaded or installed a plugin if so disable it. By default if you are using Jetpack to post to facebook from you can Disable it and use Yoast SEO plugin to SEO your post and simultaneously post to facebook as well with featured image showing.
If you have not installed any new plugins try changing the setting of the plugin you are using to post to facebook.

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Connect to the server using FTP client like CuteFTP or FileZilla and navigate to the site theme image folder. Sometimes its in wp-themes and some times the files are located in wp-content/uploads or wp-content/media and download the theme logo file you have uploaded. Make a new Logo file of same width and height and name and upload it to the same folder. FTP client will tell you file already exist do you wish to overwrite click yes and you are done. This is the best best hardcore option.