diff --git a/app/views/api/notifications/_notify_member_slot_is_canceled.json.jbuilder b/app/views/api/notifications/_notify_member_slot_is_canceled.json.jbuilder
index 5535af43c..9cb6c05f3 100644
--- a/app/views/api/notifications/_notify_member_slot_is_canceled.json.jbuilder
+++ b/app/views/api/notifications/_notify_member_slot_is_canceled.json.jbuilder
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 json.title notification.notification_type
 json.description t('.your_reservation_RESERVABLE_of_DATE_was_successfully_cancelled',
-                   RESERVABLE: notification.attached_object.reservation.reservable.name,
+                   RESERVABLE: notification.attached_object.reservation&.reservable&.name,
                    DATE: I18n.l(notification.attached_object.start_at, format: :long))