Sendible uses Facebook's Open Graph Protocol tags to generate link previews.
If the link preview looks different on Facebook or Twitter there could be few reasons for this... to help you troubleshoot these please see below:
1. Facebook has out of date link preview data
This can be the cause is most issues, due to the fact that Facebook keeps a cache of the link previews it may sometimes keep a wrong copy of them.
To fix this: You can force Facebook servers to "rescrape" (refresh) the link preview which would update their current version. Please see Facebook's Sharing Debugger to do this.
1.1 Enter the URL you're having link preview issues with and click Debug
The full URL needs to used and not the shortened URL
1.2 Scroll down to Time Scrapped and click the Scrape Again button to refresh Facebook's copy
1.3 Go back to Sendible and repost the message.
2. Duplicate or no Open Graph tags in the source code
Best practise is to have at least one Open Graph tag within the source code, please look at your URL's source code and search for how many "og:image" tags there are.
To do this, simply right click on the page in question and select "View Page Source". Then click Ctrl + F (for Windows) or Cmd + F (for Mac) and searching for how many times "og:image" appears, if any or at least it should be just once.
In some cases, this could be 2 WordPress plugins that could be causing the issue. Please ensure you are only using 1 plugin to manage your Open Graph Tags.
3. The link preview looks different on Twitter
Another thing to bear in mind is to ensure that the Open Graph information, this includes the image of course... is the same as the Twitter Card.
To check this simply right click on the page in question and select "Page Source Code".
From here you can compare all the "og:" tags with "twitter:card"
4. Still an issue?
We'll take over from here, please submit a support ticket or email firstname.lastname@example.org.
Please ensure you mention you have taken these 3 troubleshooting steps and if you can provide screenshots of the issue and the steps you took to replicate the issue, even better!