diff --git a/src/agenda_culturel/views.py b/src/agenda_culturel/views.py
index e140593..08c58a8 100644
--- a/src/agenda_culturel/views.py
+++ b/src/agenda_culturel/views.py
@@ -298,6 +298,7 @@ class EventFilter(django_filters.FilterSet):
         return self.get_cleaned_data("city")
 
     def to_str(self, prefix=''):
+        self.form.full_clean()
         result = ' '.join([c.name for c in self.get_categories()] + [t for t in self.get_tags()] + [c for c in self.get_cities()])
         if len(result) > 0:
             result = prefix + result