diff --git a/app/models/dossier.rb b/app/models/dossier.rb
index 53e3bebc0..fbef6d1a3 100644
--- a/app/models/dossier.rb
+++ b/app/models/dossier.rb
@@ -234,6 +234,7 @@ class Dossier < ApplicationRecord
   scope :termine,                     -> { not_archived.state_termine }
 
   scope :processed_in_month, -> (date) do
+    date = date.to_datetime
     state_termine
       .joins(:traitements)
       .where(traitements: { processed_at: date.beginning_of_month..date.end_of_month })