configuring webpagetest private instance for running benchmark

I have installed a private instance of webpage test in my local machine and it is connected to the Dallas server for running tests. the tutorial I followed was https://linuxhowtoguide.blogspot.com/2017/01/how-to-setup-web-page-test-private.html
currently, I am able to run normal tests. But when I try to run the included sample benchmark in my private instance it’s not showing any results.
I want to set up my custom benchmark after successfully running the included benchmark.
please, someone, have a look at the attached files and help me to identify the problem. I don’t have any coding knowledge so a detailed answer will be appreciated