登录发生错误？

LoginController.php 中添加登录验证

protected function validateLogin(Request $request)
    {
        $this->validate($request, [
            $this->username() => 'required|string',
            'password' => 'required|string',
            'captcha' => 'required|captcha',
        ], [
            'captcha.required' => '验证码不能为空',
            'captcha.captcha' => '请输入正确的验证码',
        ]);
    }

提交后，显示 错误

Type error: Argument 1 passed to App\Http\Controllers\Auth\LoginController::validateLogin() must be an instance of App\Http\Controllers\Auth\Request, instance of Illuminate\Http\Request given, called in /home/ubuntu/sites/hejinba/vendor/laravel/framework/src/Illuminate/Foundation/Auth/AuthenticatesUsers.php on line 31