When sharing blog post, excerpt is header text, and not blog summary

When I click the Facebook share icon for a blog post, the text that is used as the summary is the text from the header on the forum page, and not the meta description or the first “X” words of the blog post. The LinkedIn share button shows my meta description, so that seems to be working.

https://worklife.wharton.upenn.edu/2013/10/careers-outside-the-narrow-path/ as an example.

I’ve looked at the social plug in I’m using and there is no setting to adjust what Facebook uses as a summary. What can I do to change the text that Facebook uses to summarize my blog post when the share icon is used?

Thanks!