diff --git a/apps/participation/management/commands/fix_sympa_lists.py b/apps/participation/management/commands/fix_sympa_lists.py
index cf59963..73abb90 100644
--- a/apps/participation/management/commands/fix_sympa_lists.py
+++ b/apps/participation/management/commands/fix_sympa_lists.py
@@ -59,7 +59,8 @@ class Command(BaseCommand):
             sympa.subscribe(team.email, "equipes-non-valides", True, f"Equipe {team.name}")
 
         for participant in ParticipantRegistration.objects.filter(team__isnull=False).all():
-            sympa.subscribe(participant.user.email, f"equipe-{participant.team.trigram.lower}", True, f"{participant}")
+            sympa.subscribe(participant.user.email, f"equipe-{participant.team.trigram.lower()}",
+                            True, f"{participant}")
 
         for volunteer in VolunteerRegistration.objects.all():
             for organized_tournament in volunteer.organized_tournaments.all():