diff --git a/src/api/bot/interfaces/line.ts b/src/api/bot/interfaces/line.ts
index 0caa71ed2b..43c25f8032 100644
--- a/src/api/bot/interfaces/line.ts
+++ b/src/api/bot/interfaces/line.ts
@@ -135,6 +135,8 @@ class LineBot extends BotCore {
 				actions: actions
 			}
 		}]);
+
+		return null;
 	}
 
 	public async showUserTimelinePostback(userId: string) {