diff --git a/src/Controller/PollController.php b/src/Controller/PollController.php
index 2f55e54..f3f53c2 100644
--- a/src/Controller/PollController.php
+++ b/src/Controller/PollController.php
@@ -331,7 +331,7 @@ class PollController extends FramadateController {
 
 		if ( $found ) {
 			if ( ! $elaborated_message_version ) {
-				return $this->json( 'no-content',
+				return $this->json( null,
 					204 );
 			}
 
@@ -345,7 +345,7 @@ class PollController extends FramadateController {
 				204 );
 		}
 		if ( ! $elaborated_message_version ) {
-			return $this->json( 'NOT_found',
+			return $this->json( null,
 				404 );
 		}