"volume": 0 in "sound" of push notification payload does not make volume "0".

I use the following push notification payload.

{
 "aps": {
  "sound": {
   "name": "default",
   "volume": 0
  }
 },
 "type": "refresh"
}

When the iPhone received this, it sounds even though "volume" is set to "0".

Is this iOS bug? Or dose "default alert sound" of iOS17 override this?

I tested iOS17 and 16. This occurred both.

Is there any way to set no sound when iPhone received a specific push notification like "type": "refresh".