the following error occurred while using the mailchimp-api interface to update the mail template. The interface used is patch

program is as follows:
public function actionUpdate () {

    $tid = 48217;
    $arg = [
        "name"=> "Untitled Template",
        "html"=> "<div style="width: 700px"></div>"
    ];
    $apiKey = Yii::$app->params["apiKey"];
    $api_endpoint = Yii::$app->params["api_endpoint"];
    $MailChimp = new MailChimp($apiKey,$api_endpoint);
    $res = $MailChimp->patch("templates/".$tid);
    echo "
";
    print_r($res);
}


 Please take a look at the problem 
.