Issue coming when sending validation Errors back to page: Laravel 5.2.37

My Routes are below

Route::get('/me/{UserName}', array('uses' => 'Website\Account@index', 'as' => 'Profile'));
Route::post('/UpdateProfile', 'Website\Account@UpdateProfile');

My Request class has below code

protected function getValidatorInstance()
{
    $instance = parent::getValidatorInstance();
    $instance->after(function ($validator) {
        $this->IsValidPassword($validator);
    });
    return $instance;
}

public function IsValidPassword($validator)
{
    $Profile = \Auth::user();
    if(\Request::get( "EmailAddress" ) != $Profile->EmailAddress) {
        if(!\Hash::check(\Request::get( "Password" ), $Profile->Password)) {
            $validator->errors()->add('PasswordMismatch', 'Password is incorrect!');
        }
    }
}

public function response(array $errors){
    return \Redirect::back()->withErrors($errors);
}

Above code checks if the Password is incorrect then send the errors back to page.

Problem is : It does not go back to the page but below error is coming

HttpResponseException {#286 ▼
  #response: RedirectResponse {#289 ▶}
  #message: ""
  #code: 0
  #file: "C:\xampp\htdocs\Learning\vendor\laravel\framework\src\Illuminate\Foundation
                                                 \Http\FormRequest.php"
  #line: 107
  -trace: {▶}
}

via Chebli Mohamed