diff --git a/app/controllers/backoffice/private_formulaires_controller.rb b/app/controllers/backoffice/private_formulaires_controller.rb
index 81a728085..3c62ad362 100644
--- a/app/controllers/backoffice/private_formulaires_controller.rb
+++ b/app/controllers/backoffice/private_formulaires_controller.rb
@@ -10,7 +10,7 @@ class Backoffice::PrivateFormulairesController < ApplicationController
       if champs_service_errors.empty?
         flash[:notice] = "Formulaire enregistré"
       else
-        flash[:alert] = (champs_service_errors.inject('') { |acc, error| acc+= error[:message]+'<br>' }).html_safe
+        flash[:alert] = champs_service_errors.join('<br>').html_safe
       end
     end
 
diff --git a/app/controllers/users/description_controller.rb b/app/controllers/users/description_controller.rb
index a45a402fb..49664c5b6 100644
--- a/app/controllers/users/description_controller.rb
+++ b/app/controllers/users/description_controller.rb
@@ -38,25 +38,16 @@ class Users::DescriptionController < UsersController
                                                         params,
                                                         check_mandatory_fields
 
-      unless champs_service_errors.empty?
-        flash.alert = (champs_service_errors.inject('') { |acc, error| acc+= error[:message]+'<br>' }).html_safe
-        return redirect_to users_dossier_description_path(dossier_id: @dossier.id)
-      end
+      return redirect_to_description_with_errors(@dossier, champs_service_errors) if champs_service_errors.any?
     end
 
     if @procedure.cerfa_flag? && params[:cerfa_pdf]
       cerfa = Cerfa.new(content: params[:cerfa_pdf], dossier: @dossier, user: current_user)
-      unless cerfa.save
-        flash.alert = cerfa.errors.full_messages.join('<br />').html_safe
-        return redirect_to users_dossier_description_path(dossier_id: @dossier.id)
-      end
+      return redirect_to_description_with_errors(@dossier, cerfa.errors.full_messages) unless cerfa.save
     end
 
     errors_upload = PiecesJustificativesService.upload!(@dossier, current_user, params)
-    unless errors_upload.empty?
-      flash.alert = errors_upload.html_safe
-      return redirect_to users_dossier_description_path(dossier_id: @dossier.id)
-    end
+    return redirect_to_description_with_errors(@dossier, errors_upload) if errors_upload.any?
 
     if draft_submission?
       flash.notice = 'Votre brouillon a bien été sauvegardé.'
@@ -88,9 +79,9 @@ class Users::DescriptionController < UsersController
 
     if !((errors_upload = PiecesJustificativesService.upload!(@dossier, current_user, params)).empty?)
       if flash.alert.nil?
-        flash.alert = errors_upload.html_safe
+        flash.alert = errors_upload.join('<br>').html_safe
       else
-        flash.alert = (flash.alert + '<br />' + errors_upload.html_safe).html_safe
+        flash.alert = (flash.alert + '<br />' + errors_upload.join('<br>').html_safe).html_safe
       end
 
     else
@@ -111,6 +102,11 @@ class Users::DescriptionController < UsersController
 
   private
 
+  def redirect_to_description_with_errors(dossier, errors)
+    flash.alert = errors.join('<br>').html_safe
+    redirect_to users_dossier_description_path(dossier_id: dossier.id)
+  end
+
   def draft_submission?
     params[:submit] && params[:submit].keys.first == 'brouillon'
   end
diff --git a/app/services/champs_service.rb b/app/services/champs_service.rb
index 31b53973f..b35ec4d7b 100644
--- a/app/services/champs_service.rb
+++ b/app/services/champs_service.rb
@@ -31,11 +31,7 @@ class ChampsService
 
     def build_error_messages(champs)
       champs.select(&:mandatory_and_blank?)
-            .map { |c| build_champ_error_message(c) }
-    end
-
-    def build_champ_error_message(champ)
-      { message: "Le champ #{champ.libelle} doit être rempli." }
+            .map { |c| "Le champ #{c.libelle} doit être rempli." }
     end
   end
 end
diff --git a/app/services/pieces_justificatives_service.rb b/app/services/pieces_justificatives_service.rb
index 8dc309df8..6b10ecbeb 100644
--- a/app/services/pieces_justificatives_service.rb
+++ b/app/services/pieces_justificatives_service.rb
@@ -8,14 +8,13 @@ class PiecesJustificativesService
                                 .partition { |_, content| ClamavService.safe_file?(content.path) }
 
     errors = with_virus
-             .map { |_, content| content.original_filename + ': <b>Virus détecté !!</b><br>' }
+             .map { |_, content| content.original_filename + ': <b>Virus détecté !!</b>' }
 
     errors += without_virus
               .map { |tpj, content| save_pj(content, dossier, tpj, user) }
+              .reject(&:empty?)
 
     errors += missing_pj_error_messages(dossier)
-
-    errors.join
   end
 
   def self.upload_one! dossier, user, params
@@ -41,7 +40,7 @@ class PiecesJustificativesService
                                 type_de_piece_justificative: tpj,
                                 user: user)
 
-    pj.save ? '' : "le fichier #{pj.libelle} n'a pas pu être sauvegardé<br>"
+    pj.save ? '' : "le fichier #{pj.libelle} n'a pas pu être sauvegardé"
   end
 
   def self.missing_pj_error_messages(dossier)
@@ -49,6 +48,6 @@ class PiecesJustificativesService
     present_pjs = dossier.pieces_justificatives.map(&:type_de_piece_justificative)
     missing_pjs = mandatory_pjs - present_pjs
 
-    missing_pjs.map { |pj| "La pièce jointe #{pj.libelle} doit être fournie.<br>" }
+    missing_pjs.map { |pj| "La pièce jointe #{pj.libelle} doit être fournie." }
   end
 end
diff --git a/spec/services/champs_service_spec.rb b/spec/services/champs_service_spec.rb
index 4e8ce53a1..ee0047ea2 100644
--- a/spec/services/champs_service_spec.rb
+++ b/spec/services/champs_service_spec.rb
@@ -34,7 +34,7 @@ describe ChampsService do
       end
 
       it 'adds error for the missing mandatory champ' do
-        expect(@errors).to match([{ message: 'Le champ mandatory doit être rempli.' }])
+        expect(@errors).to match(['Le champ mandatory doit être rempli.'])
       end
     end
 
diff --git a/spec/services/pieces_justificatives_service_spec.rb b/spec/services/pieces_justificatives_service_spec.rb
index 8f10f4eb8..922befc4e 100644
--- a/spec/services/pieces_justificatives_service_spec.rb
+++ b/spec/services/pieces_justificatives_service_spec.rb
@@ -24,7 +24,7 @@ describe PiecesJustificativesService do
       let(:tpjs) { [tpj_not_mandatory] }
 
       context 'when no params are given' do
-        it { expect(errors).to eq('') }
+        it { expect(errors).to eq([]) }
       end
 
       context 'when sometihing wrong with file save' do
@@ -35,7 +35,7 @@ describe PiecesJustificativesService do
           }
         end
 
-        it { expect(errors).to eq("le fichier not mandatory n'a pas pu être sauvegardé<br>") }
+        it { expect(errors).to match(["le fichier not mandatory n'a pas pu être sauvegardé"]) }
       end
 
       context 'when a virus is provided' do
@@ -47,7 +47,7 @@ describe PiecesJustificativesService do
           }
         end
 
-        it { expect(errors).to eq('bad_file: <b>Virus détecté !!</b><br>') }
+        it { expect(errors).to match(['bad_file: <b>Virus détecté !!</b>']) }
       end
     end
 
@@ -55,7 +55,7 @@ describe PiecesJustificativesService do
       let(:tpjs) { [tpj_mandatory] }
 
       context 'when no params are given' do
-        it { expect(errors).to eq('La pièce jointe justificatif doit être fournie.<br>') }
+        it { expect(errors).to match(['La pièce jointe justificatif doit être fournie.']) }
       end
 
       context 'when the piece justificative is provided' do
@@ -74,7 +74,7 @@ describe PiecesJustificativesService do
           }
         end
 
-        it { expect(errors).to eq('') }
+        it { expect(errors).to match([]) }
       end
     end
   end