Audio keeps playing when exoplayer releases

I am using ExoPlayer in my dialog. I want the video to play automatically when dialog opens. When simpleExoPlayer.prepare() snippet is active I am able to do autoplay but when I close the dialog audio keeps playing. Before activating simpleExoPlayer.prepare() audio stops when I dismiss dialog. Is there another method to autoplay ExoPlayer or stop the audio when dialog dismiss?

class VideoViewDialog (context: Context) : BaseDialog<LayoutDialogVideoViewBinding>(context) {
    private var videoUrl : String = ""
    private lateinit var simpleExoPlayer: ExoPlayer

    override fun populateUi() {
        setCanceledOnTouchOutside(true)
        mBinding?.apply {
            initializePlayer()
        }
    }

    private fun initializePlayer() {
        val mediaDataSourceFactory: DataSource.Factory = DefaultDataSource.Factory(context)

        val mediaSource = ProgressiveMediaSource.Factory(mediaDataSourceFactory).createMediaSource(
            MediaItem.fromUri(videoUrl))

        val mediaSourceFactory: MediaSource.Factory = DefaultMediaSourceFactory(mediaDataSourceFactory)

        simpleExoPlayer = ExoPlayer.Builder(context)
            .setMediaSourceFactory(mediaSourceFactory)
            .build()

        simpleExoPlayer.addMediaSource(mediaSource)

        simpleExoPlayer.playWhenReady = true
        simpleExoPlayer.prepare()

        mBinding?.apply {
            playerView.player = simpleExoPlayer
            playerView.requestFocus()
        }
        simpleExoPlayer.play()
    }

    private fun releasePlayer() {
        simpleExoPlayer.release()
    }

    public override fun onStart() {
        super.onStart()

        if (Util.SDK_INT > 23) initializePlayer()
    }

    public override fun onStop() {
        super.onStop()

        if (Util.SDK_INT > 23) releasePlayer()
    }

    override fun getLayoutRes(): Int {
        return R.layout.layout_dialog_video_view
    }

    companion object{
        fun newInstance(
            context: Context,
            videoUrl : String,
        ) : VideoViewDialog {
            val dialog = VideoViewDialog(context)
            dialog.also {
                it.videoUrl = videoUrl
            }
            return dialog
        }
    }
}

I tried .stop, clearVideoSurface(), playerView.player = null before .release(). Didn't work it.

Seems like you called initializePlayer() twice. resulting in two Exoplayer instances playing; you're only able to release the one the simpleExoPlayer variable holds a reference to.