countActive is not a function

Hello, everyone I am trying to learn Phaser 3 by creating a small game following the official tutorial and I have a problem with the final chapter. The main character collects money and if they are all collected a new batch should appear, I am doing it by following the tutorial and when my character picks up the money the entire game freezes and I get this error in the console:

money.countActive is not a function

how come it is not a function? What am I doing wrong here? Here is how my code works:

var config = {

type: Phaser.AUTO,

width: 900,

height: 600,

physics: {

    default: 'arcade',

    arcade: {

        gravity: { y: 300 }

    }

},

scene: {

    preload: preload,

    create: create,

    update: update

}

};

var game = new Phaser.Game(config);

var score = 0;

var scoreText;

var dynamite;

function preload() {

this.load.image('sky', 'assets/world/sky.png');

this.load.image('ground', 'assets/world/ground.png');

this.load.image('platform', 'assets/world/platform.png');

this.load.image('money', 'assets/world/money.PNG');

this.load.image('dynamite', 'assets/world/dynamite.png');

this.load.spritesheet('player', 'assets/characters/player.png', { frameWidth: 32, frameHeight: 48 });

}

function create() {

this.add.image(400, 300, 'sky');

platforms = this.physics.add.staticGroup();

ground = this.physics.add.staticGroup();

platforms.create(600, 350, 'platform');

platforms.create(50, 250, 'platform');

platforms.create(650, 220, 'platform');

ground.create(500, 550, 'ground');

// Creating the player

player = this.physics.add.sprite(50, 350, 'player');

player.setBounce(0.2);

player.setCollideWorldBounds(true);

player.body.setGravityY(300)

this.physics.add.collider(player, ground);

this.physics.add.collider(player, platforms);

this.anims.create({

    key: 'left',

    frames: this.anims.generateFrameNumbers('player', { start: 0, end: 3 }),

    frameRate: 10,

    repeat: -1

});

this.anims.create({

    key: 'turn',

    frames: [{ key: 'player', frame: 4 }],

    frameRate: 20

});

this.anims.create({

    key: 'right',

    frames: this.anims.generateFrameNumbers('player', { start: 5, end: 8 }),

    frameRate: 10,

    repeat: -1

});

// Creating money

moneyStack = this.physics.add.group({

    key: 'money',

    repeat: 11,

    setXY: { x: 12, y: 0, stepX: 70 }

});

moneyStack.children.iterate(function (child) {

    child.setBounceY(Phaser.Math.FloatBetween(0.4, 0.8));

});

dynamites = this.physics.add.group();

this.physics.add.collider(moneyStack, platforms);

this.physics.add.collider(dynamites, platforms);

this.physics.add.collider(moneyStack, ground);

function collectMoney(player, money) {

    money.disableBody(true, true);

    score += 10;

    scoreText.setText('Score: ' + score);

    if (money.countActive(true) === 0) {

        //  A new batch of money to collect

        money.children.iterate(function (child) {

            child.enableBody(true, child.x, 0, true, true);

        });

        var x = (player.x < 400) ? Phaser.Math.Between(400, 800) : Phaser.Math.Between(0, 400);

        var bomb = bombs.create(x, 16, 'bomb');

        bomb.setBounce(1);

        bomb.setCollideWorldBounds(true);

        bomb.setVelocity(Phaser.Math.Between(-200, 200), 20);

        bomb.allowGravity = false;

    }

}

this.physics.add.overlap(player, moneyStack, collectMoney, null, this)

this.physics.add.collider(player, dynamites, hitDynamite, null, this);

// Creating score field

scoreText = this.add.text(16, 16, 'score: 0', { fontSize: '32px', fill: '#000' });

function hitDynamite(player, dynamite) {

    this.physics.pause();

    player.setTint(0xff0000);

    player.anims.play('turn');

    gameOver = true;

}

}

function update() {

cursors = this.input.keyboard.createCursorKeys();

if (cursors.left.isDown) {

    player.setVelocityX(-160);

    player.anims.play('left', true);

}

else if (cursors.right.isDown) {

    player.setVelocityX(160);

    player.anims.play('right', true);

}

else {

    player.setVelocityX(0);

    player.anims.play('turn');

}

if (cursors.up.isDown && player.body.touching.down) {

    player.setVelocityY(-450);

}

}

moneyStack is the group, money (in the callback) is the colliding sprite.