MouseMoveEvent stops being called - qt

Question

I'm using QCustomPlot (plot_ object) on QQuickPaintedItem (SinePlot class) so I can use it in QML. In mousePressEvent I collect initial point and in mouseMoveEvent I'm making calculations to add new points and updating cursor point:
void SinePlot::mousePressEvent(QMouseEvent* event)
{
prevPoint_ = event->globalPos();
}
void SinePlot::mouseMoveEvent(QMouseEvent* event)
{
QPointF tmp = event->globalPos();
qreal prop = (prevPoint_.x() - tmp.x()) / width();
if(prop > 0)
{
data_->shiftLeft(prop);
} else {
data_->shiftRight(prop);
}
plot_->xAxis->setRange(data_->minX, data_->maxX);
...
prevPoint_ = tmp;
update();
}
I have also trying to use pos() and localPos() but it does not make any difference, here is what I got:
As you can see mouseMoveEvent stops being called after some time(before releasing) and moving cursor does not call it.
Here is minimal reproducible example:
#ifndef SINEPLOT_H
#define SINEPLOT_H
#include "qcustomplot.h"
#include <QtQuick>
#include <QDebug>
class SinePlot : public QQuickPaintedItem
{
Q_OBJECT
public:
explicit SinePlot(QQuickItem* parent=nullptr)
{
setAcceptedMouseButtons(Qt::AllButtons);
plot_ = new QCustomPlot();
plot_->setInteractions(QCP::iRangeDrag);
plot_->addGraph();
}
virtual ~SinePlot()
{
delete plot_;
}
void paint(QPainter* painter)
{
QPicture picture;
QCPPainter qcpPainter;
qcpPainter.begin(&picture);
plot_->toPainter(&qcpPainter, width(), height());
qcpPainter.end();
picture.play(painter);
};
protected:
virtual void mousePressEvent(QMouseEvent* event) {};
virtual void mouseMoveEvent(QMouseEvent* event)
{
qDebug() << "mouse move";
};
private:
QCustomPlot* plot_;
};
#endif
In my case I got "mouse move" ~10 times.