Cannot unset string offsets

[Thu Aug 08 05:27:33.873795 2019] [php7:error] [pid 31668] [client 127.0.0.1:52104] PHP Fatal error: Uncaught Error: Cannot unset string offsets in /apps/apache/www/html/wp-content/plugins/woocommerce/includes/wc-user-functions.php:456\nStack trace:\n#0 /apps/apache/www/html/wp-includes/class-wp-hook.php(286): wc_modify_editable_roles(‘A:18:{s:13:”adm…’)\n#1 /apps/apache/www/html/wp-includes/plugin.php(203): WP_Hook->apply_filters(‘A:18:{s:13:”adm…’, Array)\n#2 /apps/apache/www/html/wp-admin/includes/user.php(242): apply_filters(‘editable_roles’, ‘A:18:{s:13:”adm…’)\n#3 /apps/apache/www/html/wp-content/plugins/js_composer/include/classes/core/access/class-vc-current-user-access-controller.php(37): get_editable_roles()\n#4 /apps/apache/www/html/wp-content/plugins/js_composer/include/classes/core/access/class-vc-role-access-controller.php(92): Vc_Current_User_Access_Controller->getRole()\n#5 /apps/apache/www/html/wp-content/plugins/js_composer/include/autoload/vc-pages/page-design-options.php(24): Vc_Role_Access_Controller->can(‘vc-color-tab’)\n#6 /apps/apache/www/html/wp-includes/class-wp-hook.php(286): vc_chec in /apps/apache/www/html/wp-content/plugins/woocommerce/includes/wc-user-functions.php on line 456