LottieAnimation start() and stop() not work as expected

import QtQuick 2.15
import QtQuick.Window 2.15
import QtQuick.Controls 2.12
import Qt.labs.lottieqt 1.0

Window {
    width: 720
    height: 720
    visible: true
    title: qsTr("Hello World")

    Button {
        id: button1
        text: "Play"
        onClicked: {
//            lottie.start()    // NOT WORK
//            lottie.gotoAndPlay(lottie.startFrame) // NOT WORK
            lottie.gotoAndPlay(2) // (sometimes gotoAndPlay(1) works, but not always)
        }
    }

    Button {
        anchors.left: button1.right
        text: "Stop"
        onClicked: {
//            lottie.stop() // NOT WORK
            lottie.gotoAndStop(lottie.endFrame)
        }
    }

    LottieAnimation {
        id: lottie
        anchors.centerIn: parent
        source: "qrc:/test01.json"
        autoPlay: false

        onStatusChanged: {
            console.log("Status Changed:" + status)
            if (status === LottieAnimation.Ready)
                start() // WORK
        }
    }
}