diff --git a/app/controllers/backoffice/dossiers_controller.rb b/app/controllers/backoffice/dossiers_controller.rb
index 14f04fe45..5c9b7f4ca 100644
--- a/app/controllers/backoffice/dossiers_controller.rb
+++ b/app/controllers/backoffice/dossiers_controller.rb
@@ -23,7 +23,8 @@ class Backoffice::DossiersController < Backoffice::DossiersListController
   end
 
   def show
-    create_dossier_facade params[:id]
+    dossier_id = params[:id]
+    create_dossier_facade dossier_id
 
     unless @facade.nil?
       @champs_private = @facade.champs_private
@@ -31,7 +32,7 @@ class Backoffice::DossiersController < Backoffice::DossiersListController
       @headers_private = @champs_private.select { |champ| champ.type_champ == 'header_section' }
     end
 
-    Notification.where(dossier_id: params[:id].to_i).update_all already_read: true
+    Notification.where(dossier_id: dossier_id).update_all already_read: true
 
     @new_avis = Avis.new(introduction: "Bonjour, merci de me donner votre avis sur ce dossier.")
   end
diff --git a/spec/controllers/backoffice/dossiers_controller_spec.rb b/spec/controllers/backoffice/dossiers_controller_spec.rb
index 169e976d6..7a647f51c 100644
--- a/spec/controllers/backoffice/dossiers_controller_spec.rb
+++ b/spec/controllers/backoffice/dossiers_controller_spec.rb
@@ -97,7 +97,7 @@ describe Backoffice::DossiersController, type: :controller do
 
       describe 'all notifications unread are changed' do
         it do
-          expect(Notification).to receive(:where).with(dossier_id: dossier_id).and_return(Notification::ActiveRecord_Relation)
+          expect(Notification).to receive(:where).with(dossier_id: dossier_id.to_s).and_return(Notification::ActiveRecord_Relation)
           expect(Notification::ActiveRecord_Relation).to receive(:update_all).with(already_read: true).and_return(true)
 
           subject