You might be calling the local implementation of the interface, instead of the actor’s function? Rename the (blue) function to avoid confusion - either your own or the editor’s.
Could this be it? If that’s not it, then the editor is drunk.
Alternatively, add a return value to the interface functions. The actors can then implement them directly without the need to create additional functions. And you get free local variables as a bonus, too; and no graph clutter.