PHP Core Warning – yii\base\ErrorException

$_GET = [
    'redirect_url' => '/yjds2016/cases/match',
];

$_COOKIE = [
    'PHPSESSID' => 'm8su5ceuhuotv2j7mnvj7m42s2',
    '_csrf' => 'bb509284d887ca1886e746d08f4940190063a46adce46a9ccb8a25430c877712a:2:{i:0;s:5:"_csrf";i:1;s:32:"2t9A7ht7066dyj8nBjoRAIkdQK-pcvuB";}',
    'topics-session' => '1791251131.316.17008.770166|d197bbbd1d400bd72372bc93068ad169',
];