cakephp cache error

//Controller
    public function index(){
        Cache::delete('fiseIndex');
        $fise = Cache::read('fiseIndex');
        if (!$fise) {
            $fise = $this->Fisa->retrieve('all',[],
                ['User','Client','SalesStatus','BrandModel'=>['Brand']]
            );
            Cache::write($fise,'fiseIndex','verylong');
        }
        $this->set('fise',$fise);
    }

//AppModel
    public function retrieve($type = 'list', $conditions = [], $contain = [], $order = []){
        if(!isset($conditions[$this->alias.'.deleted'])){
            $conditions[$this->alias.'.deleted'] = 0;
        }
        return $this->find($type,[
            'conditions' =>$conditions,
            'contain'    =>$contain,
            'order'      =>$order
        ]);
    }
//Error
Array to string conversion [M:\XAMPP\htdocs\__CORE__\lib\Cake\Cache\Engine\FileEngine.php, line 402]
//Code in CORE
 $key = Inflector::underscore(str_replace(array(DS, '/', '.', '<', '>', '?', ':', '|', '*', '"'), '_', strval($key)));