How to make display stereoscopic from monoscopic in exoplayer at android studio?

I'm trying to make stereoscopic video player in android.

but from this code, I tried copy the same simpleExoplayer instance to playerview.setPlayer functions like below.

    playerView = findViewById(R.id.player_view);
    playerViewL = findViewById(R.id.player_viewL);
    playerViewR = findViewById(R.id.player_viewR); 
    // exoPlayer = new ExoPlayer().
    simpleExoPlayer1 = new SimpleExoPlayer.Builder(this).build();
    playerView.setPlayer(simpleExoPlayer1); 
    playerViewL.setPlayer(simpleExoPlayer1); 
    playerViewR.setPlayer(simpleExoPlayer1); 
    simpleExoPlayer1.setRepeatMode(simpleExoPlayer1.REPEAT_MODE_ALL);

but this code cannot play same on triple playerview. so I wrote a new code like below.

    playerView = findViewById(R.id.player_view);
    playerViewL = findViewById(R.id.player_viewL);
    playerViewR = findViewById(R.id.player_viewR); 
    // exoPlayer = new ExoPlayer().
    simpleExoPlayer1 = new SimpleExoPlayer.Builder(this).build();
    simpleExoPlayer2 = new SimpleExoPlayer.Builder(this).build();
    simpleExoPlayer3 = new SimpleExoPlayer.Builder(this).build();
    playerView.setPlayer(simpleExoPlayer1); 
    playerViewL.setPlayer(simpleExoPlayer2); 
    playerViewR.setPlayer(simpleExoPlayer3); 
    simpleExoPlayer1.setRepeatMode(simpleExoPlayer1.REPEAT_MODE_ALL);
    simpleExoPlayer2.setRepeatMode(simpleExoPlayer2.REPEAT_MODE_ALL);
    simpleExoPlayer3.setRepeatMode(simpleExoPlayer3.REPEAT_MODE_ALL);

but from this code, their playing video was not sync for each..

I want make this playerview's sync matching and play. how do I for best?

please reply to me for some help.

thanks.