diff --git a/test/factories/checks.rb b/test/factories/checks.rb
index 27c383c..885ffd2 100644
--- a/test/factories/checks.rb
+++ b/test/factories/checks.rb
@@ -83,13 +83,5 @@ FactoryBot.define do
     trait :inactive do
       active false
     end
-
-    trait :with_notifications do
-      after :create do |check|
-        create_list :check_notification, 2,
-                    check: check,
-                    notification: build(:notification, user: check.user)
-      end
-    end
   end
 end
diff --git a/test/factories/notifications.rb b/test/factories/notifications.rb
index 434e386..6d5b348 100644
--- a/test/factories/notifications.rb
+++ b/test/factories/notifications.rb
@@ -31,7 +31,7 @@ FactoryBot.define do
     user
     interval 30
     channel :email
-    label { "#{recipient} (#{interval})" }
+    sequence(:label) { |n| "#{recipient}-#{n} (#{interval})" }
     recipient "recipient@domain.fr"
 
     trait :email do
diff --git a/test/system/checks_test.rb b/test/system/checks_test.rb
index 71e459d..14b4fb4 100644
--- a/test/system/checks_test.rb
+++ b/test/system/checks_test.rb
@@ -53,48 +53,54 @@ class ChecksTest < ApplicationSystemTestCase
     fill_and_valid_new_check
   end
 
-  test "dissociate a notification" do
-    check = create(:check, :with_notifications, user: @user)
+  test "dettach a notification from a check" do
+    initial_notifications_count = 2
+    check = create(:check, user: @user)
+    existing_notifications = create_list(:notification, initial_notifications_count, user: @user)
+    check.notifications << existing_notifications
+
     notification = create(:notification, label: "label-notification", user: @user)
     check.notifications << notification
 
     visit edit_check_path(check)
-
     uncheck notification.label
-
     click_button "Update Check"
 
     notification.reload
+    check.reload
+
     assert_equal 0, notification.checks_count
-    assert_equal 2, check.check_notifications.count
+    assert_equal initial_notifications_count, check.notifications.count
   end
 
-  test "associate a notification" do
+  test "attach a notification to a check" do
     check = create(:check, user: @user)
     notification = create(:notification, label: "label-notification", user: @user)
-    visit edit_check_path(check)
 
+    visit edit_check_path(check)
     check notification.label
     click_button "Update Check"
 
     notification.reload
+    check.reload
 
     assert_equal 1, notification.checks_count
     assert_equal 1, check.check_notifications.count
   end
 
   test "update a check" do
-    check = create(:check, :with_notifications, domain: "dom-with-notif.net", user: @user)
+    check = create(:check, domain: "dom-with-notif.net", user: @user)
+    check.notifications << create_list(:notification, 2, user: @user)
+
     visit edit_check_path(check)
-
     fill_in "check[comment]", with: "My comment"
-
     click_button "Update Check"
 
     assert_equal checks_path, page.current_path
-
     assert page.has_css?(".alert-success")
+
     check.reload
+
     assert_equal "My comment", check.comment
   end