How to stop autoplay if autoplay switch is false in Youtube iFrame API

Question

I tried various solutions like setting autoplay to 0 Adding logic to YT.PlayerState.ENDED: Changing logic for onPlayerReady()

But still nothing works. It still autoplays. Can anyone help me.

var youtubePlaylistID = "%1$s";
        var youtubeVideoID = "%1$s";
        var initialVideoIndex = %3$d;
        var mIsAutoPlay = true;
        var player;

        function onYouTubePlayerAPIReady() {
            player = new YT.Player('iframe_player_api', {
                width: videoWidth,
                height: videoHeight,
                videoId: youtubeVideoID,
                playerVars: {
                    'modestbranding': 1,
                    'showinfo': 0,
                    'rel': 0,
                    'fs': 0,
                    'autoplay': 1,
                    'controls': 0,
                    'listType': 'playlist',
                    'list': youtubePlaylistID,
                    'index': initialVideoIndex
                },
                events: {
                    'onReady': onPlayerReady,
                    'onStateChange': onPlayerStateChange
                }
            });
        }

        function onPlayerReady(event) {
            event.target.playVideo();
        }

        function onPlayerStateChange(event) {
            switch (event.data) {
                case YT.PlayerState.ENDED:
                    if(mIsAutoPlay == true) {
                        event.target.loadVideoById();
                    } else {
                        event.target.cueVideoById();
                    }
                    break;
                case YT.PlayerState.PLAYING:
                    break;
                case YT.PlayerState.PAUSED:
                    break;
                case YT.PlayerState.BUFFERING:
                    break;
                case YT.PlayerState.CUED:
                    break;
            }

I expect it to be autoplaying if mIsAutoPlay is true if false it will just stop.