QNetworkAccessManager GET. Qt application console. Wireshark does not show traffic

Question

I'm trying to get relay status for ADAM device from my Qt app. Everything seems to be working well if I run the following GET in Postman:

Wireshark shows the trace correctly:

But it does not work from my Qt application. I use QNetworkAccessManager and my code looks like this:

_networkAccessManagerPtr = new QNetworkAccessManager(this);

connect(_networkAccessManagerPtr, SIGNAL(finished(QNetworkReply*)), this, SLOT(ReplyFinished(QNetworkReply*)), Qt::DirectConnection);

SLOT:

void TestClass::ReplyFinished(QNetworkReply *reply)
{
    if (reply->error() != QNetworkReply::NoError)
    {
        qWarning() << "ERROR:" << reply->errorString();
        return;
    }
}

GET method:

bool TestClass::Get()
{
    bool aResult = false;

    QString _completeUrl = QString().append("http://").append(_ipAddress.c_str()).append(":").append(QString::number(_port)).append(URL_LOGIN.c_str());

    QString _auth = QString().append(_username.c_str()).append(":").append(_password.c_str());

    QString _headerData = QString().append("Basic ").append(_auth.toLocal8Bit().toBase64());

    _request.setUrl(QUrl(_completeUrl));
    _request.setHeader(QNetworkRequest::ContentTypeHeader, "application/x-www-form-urlencoded");
    _request.setRawHeader("Authorization", _headerData.toLocal8Bit());

    QNetworkReply * _replyPtr = _networkAccessManagerPtr->get(_request);

    _replyPtr->waitForReadyRead(-1);

    aResult = ( _replyPtr->attribute( QNetworkRequest::HttpStatusCodeAttribute ).toInt() == 200 );

    if ( !aResult )
    {
        _status = DeviceStatus::DEVICE_UNRESPONSIVE;

        qDebug() << _replyPtr->attribute( QNetworkRequest::HttpReasonPhraseAttribute ).toString();
    }
    else
    {
        _status = DeviceStatus::EVERYTHING_OK;
    }

    _replyPtr->deleteLater();

    return aResult;
}

Slot does not work, aResult=false and Wireshark does not show anything and I do not why...