Invalid layer ID (JSON-Tilemap)

[paingraph]

I want to use a tilemap i created with Tiled in JSON-format.

I'm doing everything like in the tutorials, but the the console says 

 

Tilemap.createLayer: Invalid layer ID given: null

Uncaught TypeError: Cannot read property 'resizeWorld' of undefined

 

 

Here's the code:

var game = new Phaser.Game(800, 600, Phaser.AUTO, 'gameDiv', {preload: preload, create: create, update: update});function preload(){        game.load.image('tileset', 'assets/tileset.png');    game.load.tilemap('map', 'assets/lvl1.json', null, Phaser.Tilemap.TILED_JSON);    }var map;var layer;function create(){        map = game.add.tilemap('map');    map.addTilesetImage('tileset');    layer = map.createLayer('Tile Layer 1');    layer.resizeWorld();    map.setCollisionBetween(0, 20);    }function update(){    }

What am i doing wrong ? 

sorry for my English 

[Stucky]

I also had "Invalid layer ID given: null" problem and it took me a few hours on the internet trying to solve the problem.

For me, changing the encoding of the JSON file to "CSV" instead of "base64" works. You might want to try that.