diff --git a/spec/models/post_type_spec.rb b/spec/models/post_type_spec.rb
index 144c9fe9..8b3a9463 100644
--- a/spec/models/post_type_spec.rb
+++ b/spec/models/post_type_spec.rb
@@ -88,9 +88,9 @@
     let(:kind) { 'Post' }
 
     it 'adds the custom field to the default group for posts form' do
-      field = build(:custom_field)
-      field = post_type.add_field(field.attributes, field.settings)
-      expect(post_type.get_field_object(field.slug)).to eq(field)
+      data_field = build(:custom_field)
+      field = post_type.add_field(data_field.as_json(only: %i[slug name description]), data_field.settings)
+      expect(post_type.get_field_object(data_field.slug)).to eq(field)
     end
   end
 end