找出这个生成的监听器为什么会残留处理器，而且永远不会打印 ready 消息。
csharp
using UnityEngine;
public sealed class AlarmListener : MonoBehaviour
{
private void OnEnable()
{
Alarm.Raised += code => Handle(code);
}
private void OnDisable()
{
Alarm.Raised -= code => Handle(code);
}
private void OnEnabled()
{
Debug.Log("ready");
}
private void Handle(int code) { }
}