PHP Core Warning – yii\base\ErrorException

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

$_COOKIE = [
    'PHPSESSID' => 'o3mp2a1gc3krntlcm45pt8o2f5',
    'topics-session' => '1790929843.73.16615.362794|d197bbbd1d400bd72372bc93068ad169',
    '_csrf' => 'e7594ce128e712fc53452f8a2032d907e21c67d3f34a399a17a3246f7ef15be1a:2:{i:0;s:5:"_csrf";i:1;s:32:"2iZ4J7RQoDrLDceh9N3-LCkROppnmbwr";}',
];