How does Persse miss the train to Geneva on which Angelica is traveling?

Persse rushes from Angelica's hotel to the train station with seconds to spare before Angelica's train leaves, and dashes down a staircase indicated to him by a representative; however, at the bottom of the stairs he finds that the train is on the other side of the tracks at the opposite platform, and he tries to cross the tracks but is physically restrained from doing so by security guards.