facebookはwordpressに連携できない,2018年から
wordpressのサイトにありました
ここですhttps://en.support.wordpress.com/publicize/#facebook-pages
2018年8月からfacobookに連携できません。とのことです。
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Note: Starting August 1, 2018, Facebook is making a change to their platform: third-party tools can no longer automatically share posts to Facebook Profiles. This includes Publicize. If you’ve connected a Facebook Profile to your site, then Publicize will no longer be able to share your new posts to Facebook automatically, and you won’t be able to make a new connection to a Facebook Profile. Sharing to Facebook Pages will continue to work as before.