Почему VPNService protect не работает?

Пытаюсь создать VpnClient на Android. Создал сервис:

public class VPNService extends VpnService {
	private ParcelFileDescriptor pfd;
	Thread clientReaderThread, serverReaderThread;
	private boolean stop;
	
	private ServiceBinder binder;
	
	private Socket vpnSocket;
	
	@Override
	public void onCreate() {
		super.onCreate();
		
		binder = new ServiceBinder();
	}
	
	@Override
	public int onStartCommand(Intent arg0, int arg1, int arg2) {
		VpnService.Builder vpnBuilder = new VpnService.Builder();
		vpnBuilder.addAddress("192.168.35.1", 24); 
		vpnBuilder.addRoute("0.0.0.0", 0); 
		try {
			pfd = vpnBuilder.establish();
		} catch (Exception e) {
			Log.e("MyVPN", e.toString());
		}
		new Thread(() -> {
		    try {
			vpnSocket = new Socket();
			vpnSocket.bind(new InetSocketAddress(0));
			boolean bol = protect(vpnSocket);
			vpnSocket.connect(new InetSocketAddress("178.68.14.91", 4410));
		    } catch (IOException e) {
			Log.e("MyVPN", e.toString() + " ");
		    }
		}).start();
		ClientReader clientReader = new ClientReader(new FileInputStream(pfd.getFileDescriptor()));
		ServerReader serverReader = new ServerReader(new FileOutputStream(pfd.getFileDescriptor()));
		clientReaderThread = new Thread(clientReader);
		serverReaderThread = new Thread(serverReader);
		clientReaderThread.start();
		//serverReaderThread.start();
		
		return START_NOT_STICKY;
	}
	
	public void stop() {
		if (pfd != null) {
			try {
				pfd.close();
		    } catch (IOException e) {
		    }
		}
		stop = true;
		stopSelf();
	}
	
    @Override
    public IBinder onBind(Intent intent) {
		return binder;
	}
	
	@Override
	public void onDestroy() {
		stop();
		super.onDestroy();
	}
	
	private class ClientReader implements Runnable {
		FileInputStream in;
		public ClientReader(FileInputStream in) {
			this.in = in;
		}
		@Override
		public void run() {
			byte[] buffer = new byte[4096];
			int read;
			OutputStream outStream;
			try {
			    outStream = vpnSocket.getOutputStream();
			} catch (Exception e) {
				Log.i("MyVPN", e.toString());
				return;
			}
			
			while (!stop) {
				try {
				    read = in.read(buffer);
				    outStream.write(buffer, 0, read);
				} catch (IOException e) {
					//Log.i("MyVPN", e.toString());
				}
			}
		}
	}
	
	private class ServerReader implements Runnable {
		FileOutputStream out;
		public ServerReader(FileOutputStream out) {
			this.out = out;
		}
		@Override
		public void run() {
			while (!stop) {
				
			}
		}
	}
	
	protected class ServiceBinder extends Binder {
		protected VPNService getService() {
			return VPNService.this;
		}
	}

При этом после включения VPN до IP 178.68.14.91 по сокету vpnSocket ничего не приходит. Нет даже соединения, то есть не срабатывает даже accept на ServerSocket. Хотя protect возвращает true. А если VPN убрать, то по этому сокету всё отлично доходит до получателя.