So, actually, on the museum's ticketing site they say that the internet tickets are sold out, but if you actually get there, there's a limited amount of tickets

So, actually, on the museum's ticketing site they say that the internet tickets are sold out, but if you actually get there, there's a limited amount of tickets that are sold each day (because not everyone uses the internet) : "Merci de noter que des places pour la visite le jour même sont en vente chaque jour directement à l'accueil de l'exposition, dans la limite des places disponibles.".