diff --git a/packages/backend/src/services/messages/create.ts b/packages/backend/src/services/messages/create.ts
index 4c76bee5e..b5892a891 100644
--- a/packages/backend/src/services/messages/create.ts
+++ b/packages/backend/src/services/messages/create.ts
@@ -92,7 +92,7 @@ export async function createMessage(user: { id: User['id']; host: User['host'];
 			text: message.text,
 			userId: message.userId,
 			visibility: 'specified',
-			mentions: [ recipientUser ].map(u => u.id),
+			mentions: [ recipientUser.id ],
 			mentionedRemoteUsers: JSON.stringify([ recipientUser ].map(u => ({
 				uri: u.uri,
 				username: u.username,