premise: The Portobello Film Festival is an independent international film festival based in London, which annually premiers over 700 new films, including features, shorts, documentaries, music films and animation. Additionally, workshops and talks with top film directors (such as Stephen Frears and John Maybury) are also featured. Admission to the three-week-long festival is free of charge.
hypothesis: Admission to the Portobello Film Festival is only free of charge for Stephen Frears and John Maybury.
reason: Admission is free of charge to everyone, not just those two people. System maybe didn't understand grammatical category.