PHP Core Warning – yii\base\ErrorException

$_GET = [
    'page' => '9',
];

$_COOKIE = [
    'PHPSESSID' => '93rufbmoivgjb0b62li46r8a9i',
    '_csrf' => 'df4bd399c92c3f6f479d3b9eb3c24b773d475366c8da9de33f173fa2436bf1caa:2:{i:0;s:5:"_csrf";i:1;s:32:"_paQMnNr1oTigOSWL7-q0_YxllLSJIm5";}',
];

$_SESSION = [
    '__flash' => [],
];