1 files changed, 1 insertions, 1 deletions

diff --git a/src/api/routes/read-states/ack-bulk.ts b/src/api/routes/read-states/ack-bulk.ts

index 475b223ad..bd032c087 100644
--- a/src/api/routes/read-states/ack-bulk.ts
+++ b/src/api/routes/read-states/ack-bulk.ts
@@ -28,7 +28,7 @@ router.post(
 		requestBody: "AckBulkSchema",
 		responses: {
 			204: {},
-			400: {
+			"4XX": {
 				body: "APIErrorResponse",
 			},
 		},