diff --git a/.last-synced-sha b/.last-synced-sha
index 4cc0201..97f9b43 100644
--- a/.last-synced-sha
+++ b/.last-synced-sha
@@ -1 +1 @@
-3a8ccd2466bc01294ef6a412d98863f8dd68dd43
+9f6daafb1b3a7fba595f8c76128b44cec269ae3e
diff --git a/spec/open-api-spec.yaml b/spec/open-api-spec.yaml
index a1ef717..8f70bd1 100644
--- a/spec/open-api-spec.yaml
+++ b/spec/open-api-spec.yaml
@@ -25917,6 +25917,12 @@ components:
             The timestamp when the Waitlist User was approved, or null if not
             yet approved.
           example: null
+        waitlist_id:
+          type:
+            - string
+            - 'null'
+          description: The unique ID of the Waitlist that the Waitlist User joined.
+          example: waitlist_01E4ZCR3C56J083X43JQXF3JK5
         created_at:
           format: date-time
           type: string