page object

ola pessoal

por que nao consigo usar esses asserts dentro do arquivo criado para ser o page object

<?php

namespace Src\tests\PageObject;


use Facebook\WebDriver\WebDriver;
use Facebook\WebDriver\WebDriverBy;


class PaginaLogin
{
    private WebDriver $driver;

    public function __construct(WebDriver $driver)
    {
        $this->driver = $driver;
    }

    public function realizarLoginCom(string $email, string $senha)
    {
        $this->driver->get('https://github.com/login');

        $inputEmail = WebDriverBy::id('login_field');
        $this->driver->findElement($inputEmail)->sendKeys($email);

        $inputPassword = WebDriverBy::id('password');
        $this->driver->findElement($inputPassword)->sendKeys($senha);


        $h1Locator = WebDriverBy::tagName('h1');
        $textoh1 = self::$driver->findElement($h1Locator)->getText();

        $this->assertSame('Sign in to GitHub', $textoh1);
        self::$driver->findElement(WebDriverBy::className('js-sign-in-button'))->click();

        $this->assertSame('https://github.com/', self::$driver->getCurrentURL());

        self::$driver->findElement(WebDriverBy::id('feed-original'))->getText();

    }
}

no arquivo loginTest, esses asserts nao dao erro, o e teste roda certinho, porem qdo coloco dentro da funcao realizarLoginCom da erro...