This can happen for multiple reasons, but don't worry.
1) Try to use the Social Media Platform's Debug Tools
It could be that the Social Media Platforms have not checked your site for a new image yet. You can tell them to do that!
Facebook Debugger Tool
Go to the Facebook Debugger Tool, enter the URL of your article and click "Debug". You will see which information Facebook has about your post at the moment, including your image that might be missing. Then click "Scrape again". Your new image should now be displayed.
Twitter Card Validator
Go to the Twitter Card Validator, enter the URL of your article and click "Preview Card". You will see a preview of how the link will look like when shared in a tweet. Your new image should now be displayed.
LinkedIn Post Inspector
Go to the LinkedIn Post Inspector, enter the URL of your article and click "Inspect". You will see a preview of how the link will look like when shared on LinkedIn. Your new image should now be displayed.
Pinterest URL Debugger
Go to the Pinterest URL Debugger, enter the URL of your article and click "Validate". Try pinning your article on Pinterest again. Your new image should now be displayed.
Did your image still not show up? Then try this:
2) Check the Placid image generation status in WordPress
Open your blog article while logged in to WordPress. Open the Social Share Preview box to preview your article.
If you see a loading spinner, this means that your image is still being generated by Placid. Please try reloading a few minutes later. Repeat until the loading spinner is gone and you can see your image.
If your image is now showing up in the Social Share Preview in WordPress but not on Social Media, please repeat step 1!
3) Check your Placid settings in WordPress
Go to Tools > Placid Social Images > Setup in WordPress and check if your license key is valid. If it is, please check if you have turned on the automatic image creation through Placid. There should be an active checkbox in either the OG Images, Twitter or Pinterest tab: Set Open Graph Images with Placid / Set Twitter Card Images with Placid / Set Pinterest Images with Placid
4) Check for interfering plugins
If you have used another plugin to set Social Images until now (like Yoast, Thumb Fixer, Social Pug or Social Warfare) and it is still active, Placid will not override their settings. This makes sure that your older articles will still display images that you uploaded manually instead of a generated one. (You already put a lot of work into those!)
If you want to override all Social Images on your blog with Placid, go to Tools > Placid Social Images > Setup in your WordPress admin interface and activate the two checkboxes under Advanced Settings:
- Remove og:image Tags
- Remove twitter:image Tags
If none of these solutions worked, it could be that the Social Platforms won't let you change the Share Images for some of your articles any more because they have already been shared a lot. They will sometimes keep the first share image of popular articles to not confuse users that shared your post.
Please check on a newer entry that has not yet been shared a lot!