Why is the page or data not displayed on post request with rest api?

Question

Yii

I have config in api/config/main.php

'urlManager' => [
            'enablePrettyUrl' => true,
            'enableStrictParsing' => true,
            'showScriptName' => false,
            'rules' => [
          [
                    'class' => 'yii\rest\UrlRule',
                    'controller' => ['v1/auth'],
                    'pluralize' => false,
                    'extraPatterns' => [
                        'POST auth' => 'auth/index',
                    ]
                ],
            ],
        ],

But in this situation, in a get request, it normally works for me, but with a post request, it already gives a 404 error code.

namespace api\modules\v1\controllers;

class AuthController extends ApiController
{
    /**
     * @brief Авторизация
     */
    public function actionIndex()
    {
        var_dump("hello"); die();
    }
}

Why exactly such an incomprehensible event occurs?