Hi @tataye,
Open the default.php file in the "shape5_vertex/html/mod_articles_latest/" folder and change code from:
...
defined('_JEXEC') or die;
?>
<ul class="latestnews<?php echo $moduleclass_sfx; ?> mod-list">
...to
...
defined('_JEXEC') or die;
$moduleclass_sfx = $params->get('moduleclass_sfx','');
?>
<ul class="latestnews<?php echo $moduleclass_sfx; ?> mod-list">
...Save and reload your site.