Nulab API Integration Engineer interview questions

I first had a Skype interview with their HR in New York which went well. After that they sent me an assignment and gave me a week to finish it. I finished the assignment before the deadline and emailed it to them asking for a feedback! They didn't reply to my email. After almost a month I sent another email to their HR in New York asking for a feedback to which again they didn't reply! I think every candidate deserves a feedback regardless of how good or bad they did on assignment and yeah I definitely had a negative experience because of that! I hope they show more respect to their future applicants!