iOS local push notification header missing

i am using the notification server Unity API to push local notification (https://docs.unity3d.com/ScriptReference/iOS.LocalNotification.html), however, I cannot find out how to set the header notification via this API? Does Unity support this or I have to write my own plugin using iOS native function?

 

What is the header?

 

Sorry, I mean the title of notification like this in this payload
https://developer.apple.com/library...cationsPG/CreatingtheNotificationPayload.html

 

The alertAction field is the title.