When I am in Lightroom Publishing Manager, there are times when I try to click into and I get messages that I cannot connect with Facebook with the Plug in Manager and I used that manager the day before. In the past I created a new plug in manager however then I cannot add pictures to an existing album on Facebook. Do you have any suggestions on how to reconnect that plug in manager to FB?
Please ensure Lightroom is up to date.
Reauthorize your Account in Lightroom and check if that helps.
Also you may refer Unable to set up facebook in publish service | Lightroom Forums