diff --git a/app/Util/ActivityPub/Helpers.php b/app/Util/ActivityPub/Helpers.php
index 8154a6ca..3a73c1a9 100644
--- a/app/Util/ActivityPub/Helpers.php
+++ b/app/Util/ActivityPub/Helpers.php
@@ -210,7 +210,7 @@ class Helpers {
 				$activity = ['object' => $res];
 			}
 
-			$idDomain = parse_url($activity['id'], PHP_URL_HOST);
+			$idDomain = parse_url($res['id'], PHP_URL_HOST);
 			$urlDomain = parse_url($url, PHP_URL_HOST);
 			$actorDomain = parse_url($activity['object']['attributedTo'], PHP_URL_HOST);