答：

没有错code ..

Nothing wrong with the code..

这只是愚蠢的iPhone并没有取消，我的默认声音发旧的通知 - _ 的 - ;

It's just that the stupid iPhone didn't cancel the old notifications that I made with the default sound -_-;

当我清理项目，从手机中删除的应用，然后重新启动手机，它的工作。

When I cleaned the project, deleted the app from the phone AND REBOOTED the phone THEN it worked..

希望有人认为这很有帮助。

Hope someone finds this helpful.