Fecthing associated model with find contain

1

My school model has a many to many relationship with my attribute model joined by attribute_school table
In my Shell folder for cron job i have the following in my main function

        $schoolsRaw = TableRegistry::get('Schools');

        $schools = $schoolsRaw->find('all', ['fields'=>['Schools.name','Schools.logo','Schools.discount''],    
                                                             'contain'=>['Users'=> ['fields'=>['Users.first_name', 
                                                             'Users.last_name','Users.email', 'Users.title']], 'Attributes'=>
                                                            ['fields'=>['Attributes.model']]]]);


       echo debug(json_encode($schools , JSON_PRETTY_PRINT));

The above echo commands keep generating empty values for all instance of the school record like this

{
“name”: “Genesis School”,
“logo”: “badges/genesis.jpg”,
“discount”: “Not Stated”,
“attributes”: [],
“user”: {
“first_name”: “xxxxx”,
“last_name”: “yyyyy”,
“email”: "mynane@yahoo.co.uk",
“title”: “Ms”
}

My models
//schools
public function initialize(array $config)
{
parent::initialize($config);

    $this->setTable('schools');
    $this->setDisplayField('name');
    $this->setPrimaryKey('id');

    $this->belongsTo('Users', [
        'foreignKey' => 'user_id',
        'joinType' => 'INNER'
    ]);
    $this->belongsToMany('Attributes', [
        'foreignKey' => 'school_id',
        'targetForeignKey' => 'attribute_id',
        'joinTable' => 'attributes_schools'
    ]);
}

// attributes model
public function initialize(array $config)
{
parent::initialize($config);

    $this->setTable('attributes');
    $this->setDisplayField('name');

    $this->belongsToMany('Schools', [
        'foreignKey' => 'attribute_id',
        'targetForeignKey' => 'school_id',
        'joinTable' => 'attributes_schools'
    ]);
}

// join table
public function initialize(array $config)
{
parent::initialize($config);
$this->primaryKey(‘id’);
$this->setTable(‘attributes_schools’);

    $this->belongsTo('Schools', [
        'foreignKey' => 'school_id',
        'joinType' => 'INNER'
    ]);
    $this->belongsTo('Attributes', [
        'foreignKey' => 'attribute_id',
        'joinType' => 'INNER'
    ]);
}

This is cakephp 3.4 and I don’t know why it is not fetching attributes records and no bug is logged. Please help