Callkit outgoing UI not shows anymore from ios14

Before ios14, when use startCallAction, lock iphone, it will shows callkit outgoing system UI.

But in ios14, this UI never shows. Only when connected to carplay, I can see this UI again.

So I'd like to know is this a bug or its new design ? This behavior affect my app, needs your help, Thanks.

Demo code:

  CXStartCallAction *action = [[CXStartCallAction alloc] initWithCallUUID:uuid handle:handle];       CXTransaction *transaction = [CXTransaction new];   [transaction addAction:action];       [controller requestTransaction:transaction completion:^(NSError * _Nullable error)

Callkit outgoing UI not shows anymore from ios14
 
 
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