ReplayKit can not include user commentary and camera footage while broadcasting

The code is below:

 public class buttons : MonoBehaviour {
 
     void Start () {
         ReplayKit.cameraEnabled = true;
         ReplayKit.microphoneEnabled = true;
     }
 
     void OnGUI ()
     {
         GUI.Box (new Rect (2 * 10, 2 * 10, 2 * 200, 4 * 90), "Broadcasting");
 
         if (GUI.Button (new Rect (2 * 20, 2 * 40, 2 * 180, 2 * 30), "Start Broadcasting")) {
             
             ReplayKit.StartBroadcasting ((bool success, string error) => Debug.Log (string.Format ("Start : {0}, error : `{1}`", success, error)),true,true);
             showRet=ReplayKit.ShowCameraPreviewAt (50, 50);
         }
         if (GUI.Button (new Rect (2 * 20, 2 * 70, 2 * 180, 2 * 30), "Stop Broadcasting")) {
             ReplayKit.StopBroadcasting();        
         }
 
     }
 }

Broadcasting is started successfully,but can not include user commentary and camera footage.I have written privacy description in info.plist,but it seems that camera and microphone are not enabled. Does anyone know how to use UnityEngine.Apple.ReplayKit? Thanks!