Ok, so it seems your build is pretty old and does not reflect the current way Facebook's API works.
You can have a look at the Campaign release notes here: Adobe Campaign Release Notes
By searching for "social", you will see that some builds more recent than yours contain fixes related to Facebook's API evolution.
I would recommend upgrading to a more recent build, by reaching out to your IT department if you are on-prem or to Campaign support team if you are hosted.
Hope this helps,
Florent.