code to implement correct validation

app/models/scheme.rb

@@ -5,8 +5,6 @@ class Scheme < ApplicationRecord
   has_many :locations
   has_many :case_logs
 
-  validates :organisation_id, presence: { message: I18n.t("validations.scheme.id_missing") }
-
   scope :search_by_code, ->(code) { where("code ILIKE ?", "%#{code}%") }
   scope :search_by_service_name, ->(name) { where("service_name ILIKE ?", "%#{name}%") }
   scope :search_by_postcode, ->(postcode) { joins(:locations).where("locations.postcode ILIKE ?", "%#{postcode.delete(' ')}%") }

config/locales/en.yml

@@ -38,10 +38,15 @@ en:
     create_password: "Create a password to finish setting up your account"
     reset_password: "Reset your password"
 
-  validations:
+  activerecord:
+    errors:
+      models:
         scheme:
-      id_missing: "Enter the organisation’s name"
+          attributes:
+            organisation:
+              required: "Enter the organisation’s name"
 
+  validations:
     organisation:
       name_missing: "Enter the organisation’s name"
       provider_type_missing: "Select the organisation’s type"

spec/models/scheme_spec.rb

@@ -8,6 +8,11 @@ RSpec.describe Scheme, type: :model do
       expect(scheme.organisation).to be_a(Organisation)
     end
 
+    it "validates organisation_id presence" do
+      expect { FactoryBot.create(:scheme, organisation: nil) }
+        .to raise_error(ActiveRecord::RecordInvalid, "Validation failed: Provider type #{I18n.t('validations.scheme.id_missing')}")
+    end
+
     describe "scopes" do
       let!(:scheme_1) { FactoryBot.create(:scheme) }
       let!(:scheme_2) { FactoryBot.create(:scheme) }

spec/requests/schemes_controller_spec.rb

@@ -594,7 +594,7 @@ RSpec.describe SchemesController, type: :request do
         it "displays the new page with an error message" do
           post "/schemes", params: params
           expect(response).to have_http_status(:unprocessable_entity)
-          expect(page).to have_content(I18n.t("validations.organisation.name_missing"))
+          expect(page).to have_content(I18n.t("activerecord.errors.models.scheme.attributes.organisation.required"))
         end
       end
     end