Rendering Error after login

Rendering Error in layout Widget/Module: Call to a member function cachedCompile() on null. Please enable debug mode for more information.

Rendering Error in layout Widget/Module: Call to a member function cachedCompile() on null in /var/www/vhosts/transalpclub.nl/kunena.transalpclub.nl/plugins/system/helix3/core/helix3.php on line 774
Layout was rendered in /var/www/vhosts/transalpclub.nl/kunena.transalpclub.nl/components/com_kunena/template/crypsisb3/layouts/page/default.php on line 25

	public static function addLess($less, $css, $attribs = array())
	{
		$template  = JFactory::getApplication()->getTemplate();
		$themepath = JPATH_THEMES . '/' . $template;

		if (self::getParam('lessoption') and self::getParam('lessoption') == '1')
		{
			if (file_exists($themepath . "/less/" . $less . ".less"))
			{
-->				self::getInstance()->autoCompileLess($themepath . "/less/" . $less . ".less", $themepath . "/css/" . $css . ".css");
			}
		}
		self::getInstance()->addCSS($css . '.css', $attribs);

		return self::getInstance();
	}

	if ($config->get('displayModule'))
	{
-->		echo $this->subLayout('Widget/Module')->set('position', 'kunena_top');
	}

<div id="kunena" class="layout <?php echo $this->options->get('pageclass_sfx'); ?>">
	<?php