Flutter Binance API user data stream

I am using an unofficial dart wrapper for Binance Spot API and when I input my API key and secret key and run the simulator I get the following error: Last userdateStream event: Binance API returned error -2014: API-key format invalid. Can anyone help?

class _HomePageState extends State<HomePage> {
  BinanceSpot binanceSpot = BinanceSpot(
    key: "<apiKey>",
    secret: "<apiSecret>",
  );
  double lastClosePrice = 0;
  String tradablePairs = "";
  String lastEventData = "";
  late StreamSubscription<dynamic> klineStreamSub;
  late StreamSubscription<dynamic> userdataStreamSub;
  @override
  void initState() {
    startKlineStream();
    startUserdataStream();
    super.initState();
  }


  void startUserdataStream() async {
    var response = await binanceSpot.createListenKey();
    if (response.isRight) {
      var stream = binanceSpot.userDataStream(listenKey: response.right);
      userdataStreamSub = stream.listen(handleUserdataEvent);
    } else {
      lastEventData = response.left;
    }
  }

  void handleUserdataEvent(dynamic event) {
    if (event is WsAccountUpdate) {
      lastEventData = "Account update event : ${event.balances.length} balances updated";
    } else if (event is WsBalanceUpdate) {
      lastEventData = "Balance update event : ${event.asset} balance updated";
    } else if (event is WsExecutionReport) {
      lastEventData = "Execution report event : status is ${event.orderStatus.toStr()}";
    } else if (event is WsListOrderStatus) {
      lastEventData = "ListOrder update event : status is ${event.listOrderStatus}";
    } else {
      lastEventData = "Unknown event type : ${event.toString()}";
    }
  }