Any suggestion what i should do in this case?
Is the connected node enough, or does it require the target connection, because it works when you add the Actor component, but then no PlayerState input connection. This happened after changing the PlayerFrame, which lead to a succession of failure 
Added a fresh copy of the 4.14 release into my project, moved the SocialComponent, opened it, and the same node is broken.
This fixes it, but is it enough?
Also this node is broken on restart (Changed the related PlayerState reference for my project, after the error became visible). Also changed then the SPlayer structure PlayerState, still the error is there.
Okay, above error can be fixed, when just connecting the node, closing the editor, then delete Saved and Intermediate folder, restarting. Problem gone.