Your domain only works with the www version, so it seems like your DNS records are corrupted. Can you try to remove your domain and then re-add it again on the “Addon Domains” section of the Control Panel, then upload your website files on the new document root the system has created (so uczhesap.ml/htdocs/)? That should fix the issue, but even then the www version of the domain also throws a HTTP ERROR 500, so after solving this read this article to solve the other error: