I am enclosing the code of my class for working with magnetic fields.
Tell me, please, what am I doing wrong?
Developed for IOs, version Qt 5.15.
Thank!

    #ifndef MAGNETO_H
    #define MAGNETO_H
     
    #include <QObject>
     
    #include <QMagnetometer>
    #include <QMagnetometerFilter>
    #include <QMagnetometerReading>
    #include "math.h"
     
    #include <QDebug>
     
    class Magneto : public QObject, public QMagnetometerFilter
    {
        Q_OBJECT
    public:
        explicit Magneto(QObject *parent = nullptr);
        ~Magneto();
     
        bool filter(QMagnetometerReading *reading);
     
        void start();
        void stop();
        bool isMagnetoStarted();
     
    private slots:
        void onSensorError(const int &errorCode);
     
    signals:
        void dataReceived(const qreal &x,
                          const qreal &y,
                          const qreal &z);
     
    private:
        QMagnetometer *m_magnetometer;
        qreal m_x;
        qreal m_y;
        qreal m_z;
        bool m_isStarted;
    };
     
    #endif // MAGNETO_H

    #include "magneto.h"
     
    Magneto::Magneto(QObject *parent) : QObject(parent)
    {
        m_magnetometer = new QMagnetometer(this);
        m_magnetometer->addFilter(this);
        m_magnetometer->setReturnGeoValues(true);
     
        connect(m_magnetometer, SIGNAL(sensorError(int)),
                this, SLOT(onSensorError(int)));
     
        m_isStarted = false;
    }
     
    Magneto::~Magneto()
    {
        m_magnetometer->deleteLater();
    }
     
    bool Magneto::filter(QMagnetometerReading *reading)
    {
        qDebug() << reading->calibrationLevel() << reading->x() << reading->y() << reading->z();
     
        emit dataReceived(reading->x() * pow(10, 6),
                          reading->y() * pow(10, 6),
                          reading->z() * pow(10, 6));
    }
     
    void Magneto::onSensorError(const int &errorCode)
    {
        qDebug() << errorCode;
    }
     
    void Magneto::start()
    {
        m_isStarted = true;
        m_magnetometer->start();
    }
     
    void Magneto::stop()
    {
        m_isStarted = false;
        m_magnetometer->stop();
    }
     
    bool Magneto::isMagnetoStarted()
    {
        return m_isStarted;
    }