If your groups and pages don't show up on in the facebook connections - 

it's likely because it's a new page or a new group that has been created after the original pemissions were granted by the app. 

these steps will resolve it for you . 

Log into facebook, 
then go to settings
then to 'settings and privacy' 
then to settings - within that menu
then to security and login
and business integrations. 
then - search for Social Post Magic 
and remove the app.

then log back into Social Post Magic
And click to add a new facebook connection -
And because the app has been removed it will prompt you to re-authorise your permissions
And all pages and groups will show up.

Apologies that this is a few steps but - it's a facebook thing not from our end.