Hello,

1. Actually, you have added the incomplete shortcode in the Theme Settings >> Footer >> Copyright section, which created the issue, I have deleted that incomplete code and the slider is working fine.

2. Also, I did not see any issue on the page the WP Bakery editor is working fine:
https://safetymunkaruha.hu/wp-admin/post.php?vc_action=vc_inline&post_id=29&post_type=page

Best Regards.