Fatal error: Uncaught TypeError: Cannot access offset of type string on string i

I have just updated Yith plugins (yith-essential-kit) and getting the errors below:

Fatal error: Uncaught TypeError: Cannot access offset of type string on string in /usr/www/users/riaanjrgfh/wp-content/plugins/yith-essential-kit-for-woocommerce-1/plugin-fw/includes/class-yit-plugin-panel.php:294 Stack trace: #0 /usr/www/users/riaanjrgfh/wp-content/plugins/yith-essential-kit-for-woocommerce-1/plugin-fw/includes/class-yit-plugin-panel.php(1542): YIT_Plugin_Panel->maybe_init_vars() #1 /usr/www/users/riaanjrgfh/wp-content/plugins/yith-essential-kit-for-woocommerce-1/plugin-fw/includes/class-yit-plugin-panel.php(1305): YIT_Plugin_Panel->get_main_array_options() #2 /usr/www/users/riaanjrgfh/wp-includes/class-wp-hook.php(308): YIT_Plugin_Panel->add_fields(”) #3 /usr/www/users/riaanjrgfh/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(NULL, Array) #4 /usr/www/users/riaanjrgfh/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #5 /usr/www/users/riaanjrgfh/wp-admin/admin.php(175): do_action(‘admin_init’) #6 /usr/www/users/riaanjrgfh/wp-admin/plugins.php(10): require_once(‘/usr/www/users/…’) #7 {main} thrown in /usr/www/users/riaanjrgfh/wp-content/plugins/yith-essential-kit-for-woocommerce-1/plugin-fw/includes/class-yit-plugin-panel.php on line 294