Pagebuilder dont works

Pagebuilder plugin dont works, use wp version 4.9.1

AH01071: Got error ‘PHP message: PHP Fatal error: Uncaught Error: [] operator not supported for strings in /var/www/vhosts/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/wp-content/plugins/wlt_builder/includes/admin/PT_Options.php:15\nStack trace:\n#0 /var/www/vhosts/xxxxxxxxxxxxxxxxxxxxxxxxx/wp-content/plugins/wlt_builder/shortcodes/PT_Section.php(143): PT_Options->__construct(Array)\n#1 /var/www/vhosts/xxxxxxxxxxxxxxxxxxxxxxxxxxx/wp-content/plugins/wlt_builder/pt-builder.php(216): PT_Section->shortcode_options(Array)\n#2 /var/www/vhosts/xxxxxxxxxxxxxxxxxx/wp-includes/class-wp-hook.php(286): pt_add_new(”)\n#3 /var/www/vhosts/xxxxxxxxxxxxxx/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(”, Array)\n#4 /var/www/vhosts/xxxxxxxxxxxxxxxxxxxxxxxxx/wp-includes/plugin.php(453): WP_Hook->do_action(Array)\n#5 /var/www/vhosts/xxxxxxxxxxxxxxx/wp-admin/admin-ajax.php(97): do_action(‘wp_ajax_pt_add_…’)\n#6 {main}\n thrown in /var/www/vhosts/xxxxxxxxxxxxxxxxxx/wp-content/plugins/wlt_builder/incl…\n’, referer: https://xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/wp-admin/post.php?post=11094&action=edit

need hlp

thx