diff --git a/src/index.ts b/src/index.ts
index a45676e..b289928 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -109,7 +109,7 @@ const KidShiftTaskCompleteIntentHandler = {
         const attributeUtils = new AttributeUtils(handlerInput);
         TaskService.setToken(await attributeUtils.getToken());
 
-        TaskService.completeTask(task.id, child.id).then(() => {
+        return TaskService.completeTask(task.id, child.id).then(() => {
             return handlerInput.responseBuilder
                 .speak('Task completed')
                 .getResponse();
@@ -117,10 +117,6 @@ const KidShiftTaskCompleteIntentHandler = {
             return handlerInput.responseBuilder
                 .speak('Task completion failed')
                 .getResponse();
-        }).finally(() => {
-            return handlerInput.responseBuilder // ここに到達することはないはず
-                .speak('Task completion failed(UNKNOWN)')
-                .getResponse();
         });
     }
 };