Sharing a page from your website and the preview picture and/or text is not updating, even after you fix it?
This is because Facebook has cached your previous images and SEO information for that particular page. In order to debug and clear everything, you will need to debug that particular URL and "SCRAPE" that page using the Facebook Sharing Debugger tool.
How does the Facebook Crawler work?
You can use the Sharing Debugger to see the information that is used when your website content is shared on Facebook, Messenger and other places. The Batch Invalidator will let you refresh this information for multiple URLs at the same time.
Steps to Scrape your URL:
Open the Facebook Sharing Debugger
Paste the URL that you wish to clear the cache for
Click the button to Debug
Click the button to Scrape (sometimes you need to click it a few times for it to update)
Go try and share your URL again and voila!