diff --git a/app/controllers/api/v1/registrant/contacts_controller.rb b/app/controllers/api/v1/registrant/contacts_controller.rb
index 31d56885b..f252b3acd 100644
--- a/app/controllers/api/v1/registrant/contacts_controller.rb
+++ b/app/controllers/api/v1/registrant/contacts_controller.rb
@@ -31,7 +31,7 @@ module Api
           if @contact
             render json: @contact
           else
-            render json: { errors: ['Contact not found'] }, status: :not_found
+            render json: { errors: [{ base: ['Contact not found'] }] }, status: :not_found
           end
         end
 
diff --git a/test/integration/api/registrant/registrant_api_contacts_test.rb b/test/integration/api/registrant/registrant_api_contacts_test.rb
index a3367dd58..ff51494af 100644
--- a/test/integration/api/registrant/registrant_api_contacts_test.rb
+++ b/test/integration/api/registrant/registrant_api_contacts_test.rb
@@ -50,7 +50,7 @@ class RegistrantApiContactsTest < ActionDispatch::IntegrationTest
     assert_equal(401, response.status)
     json_body = JSON.parse(response.body, symbolize_names: true)
 
-    assert_equal({ errors: ['Not authorized'] }, json_body)
+    assert_equal({ errors: [base: ['Not authorized']] }, json_body)
   end
 
   def test_details_returns_401_without_authorization
@@ -58,7 +58,7 @@ class RegistrantApiContactsTest < ActionDispatch::IntegrationTest
     assert_equal(401, response.status)
     json_body = JSON.parse(response.body, symbolize_names: true)
 
-    assert_equal({ errors: ['Not authorized'] }, json_body)
+    assert_equal({ errors: [base: ['Not authorized']] }, json_body)
   end
 
   def test_details_returns_404_for_non_existent_contact
@@ -66,7 +66,7 @@ class RegistrantApiContactsTest < ActionDispatch::IntegrationTest
     assert_equal(404, response.status)
     json_body = JSON.parse(response.body, symbolize_names: true)
 
-    assert_equal({ errors: ['Contact not found'] }, json_body)
+    assert_equal({ errors: [base: ['Contact not found']] }, json_body)
   end
 
   private