TiledMap.setTiledGIDAt not work!

Hi, guys.
Im trying to create game with isometric tiledmap and im using Tiled app to create the map. Everything work fine till i’m trying to change a tiled at runtime via setTileGIDAt. Nothing happen after I call the function, no error, no warning or anything. Did I do something wrong?

// map 3x3
updateTile(){
    let col = 2;
    let row = 1;
    let layer = this.tiledMap.getLayer("Demo");
    layer.setTileGIDAt(1, col, row);
}

@pandamicro can you help me, pls!