Rich subject or a parameter for "{user} ... {card} ... {stack} ... {board}" is malformed

Hi, not sure I’m posting this post in the right category…

Some notifications from Deck are correct, some are not. For instance (text in french where some values have been anonymised):

Aujourd’hui 09:58
NamedUser a mis à jour la date d’échéance de la carte Deck card name à 4 avril 2021 08:00:00 UTC+0

Aujourd’hui 10:00
Rich subject or a parameter for “{user} a mis à jour la description de la carte {card} de la liste {stack} du tableau {board}” is malformed

What’s wrong with the second line?