not working gantt_data xml file after composer update

Hi, I am developed dhtmlxGantt using laravel under dhtmlx.com tutorials. but it is not display gantt_data xml file when I load it, after that I download direct link zip file in tutorial under create a data source and it is working properly. but after composer update on app it also not working gantt_data xml file (not view database data) any one can give a solution to fix this problem.

Thanks.