swift - 即使 content-available = 1，也没有在后台 iOS 14 中调用 didReceiveRemoteNotification

Question

不幸的是，我用完了问题限制，所以我不得不编辑这个以前提出的问题，以获得社区的帮助。问题是 fetchCompletionHandler 在 iOS 14 后台停止工作，收到推送通知但此函数在用户交互之前不会调用。我想知道会出现什么问题，因为我已经添加了 iOS 13 中推荐的标头值，并且推送通知有效负载如下但仍然没有成功；

[AnyHashable("aps"): {
alert =     {
    body = "Hi, you have received a notification;
    title = "You have received a notification";
};
"content-available" = 1;
"mutable-content" = 1;
sound = default;},AnyHashable("extraPayLoad"): {
action = "cl_blocked";
"read_id" = "123";
"short_msg" = "You have received a notification";}]

plist 也是这样的；

<key>UIBackgroundModes</key>
<array>
    <string>bluetooth-central</string>
    <string>processing</string>
    <string>remote-notification</string>
</array>

有谁知道如何解决这个问题。