networkAccessibleChanged signal never gets called

[INeedADollar]

Hello! I am trying to detect when I lose connection to Internet, for example when I cannot load any site or any application that connects to Internet.
I am trying this with QNetworkAccesManager but signal networkAccessibleChanged never gets called.

My code:

mainWindow::mainWindow(QWidget *parent) : QWidget(parent)
{
    this->setGeometry(400, 400, 400, 400);
    manager = new QNetworkConfigurationManager();
    pManager->setConfiguration(manager->defaultConfiguration());
    connect(pManager, &QNetworkAccessManager::networkAccessibleChanged, this, &mainWindow::test);
}
 
void mainWindow::test(QNetworkAccessManager::NetworkAccessibility access){
    qDebug() << access;
}

mainWindow::mainWindow(QWidget *parent) : QWidget(parent)
{
    this->setGeometry(400, 400, 400, 400);
    manager = new QNetworkConfigurationManager();
    pManager->setConfiguration(manager->defaultConfiguration());
    connect(pManager, &QNetworkAccessManager::networkAccessibleChanged, this, &mainWindow::test);
}

void mainWindow::test(QNetworkAccessManager::NetworkAccessibility access){
    qDebug() << access;
}

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How can I solve this? Thank you!