Problem with same webform added multiple time in a page

Problem

I have an Article node with layout builder enabled for content author.

I have webform Subscribe newsletter with ajax enabled.

I add webform Subscribe newsletter to the node twice. So there are 2 same webform added to the node.

When I submit the second form, the confirmation message appear in the first webform.

Expected

Confirmation message should appear in second webform.

What I tried

I tried to change the id by using

function MY_MODULE_form_alter(&$form, FormStateInterface $form_state, $form_id) {
    if (isset($form['#webform_id'])) {
      $counter = _MY_MODULE_generate_webform_unique_id($form['#webform_id']);

      if ($counter !== 0) {
        $new_id = $form_id . '_' . $counter;
        $form['#form_id'] = $new_id;
        $form['#attributes']['id'] = $new_id;
        $form['#form_wrapper_id'] = $form['#form_wrapper_id'] . '--' . $counter;

        $content_wrapper = $form['#form_wrapper_id'] . '-content--' . $counter;
        $wrapper_id = $form['#form_wrapper_id'] . '--' . $counter;
        $prefix = '<span id="'. $content_wrapper .'"></span>' .
          '<div id="' . $wrapper_id . '" class="webform-ajax-form-wrapper" data-effect="fade" data-progress-type="throbber">';
        $form['#prefix'] = $prefix;
      }
    }
}


function _MY_MODULE_generate_webform_unique_id($webform_id) {
  $static_var = &drupal_static(__FUNCTION__ . ':' . $webform_id);
  if (!isset($static_var)) {
    // generate contents of static variable
    $static_var = 0;
  }
  else {
    $static_var += 1;
  }

  return $static_var;
}

I can change the form ID, but the confirmation message still display in the first webform.

I saw similar in here https://drupal.stackexchange.com/a/272176/26797 but this is for custom form. Not sure how to apply it with webform.

Is there some mistake that I made or other approach?

Thank in advance.

Edit

For quick workaround, I currently change all form to display in Drupal modal dialog. So instead of form appear in the page, I put a link and user click the link to open the form. Not sure if this is a bug in webform or my custom code is messing up stuff. I will need to try this in vanilla Drupal later on.