CPower Energy Management Associate, Business Development interview questions

Very negative experience interviewing with CPower. I was excited about the role, and after a very short (15 min) intro call with the hiring manager, I was asked to complete a BESS modeling and presentation assignment -- and was told that after submitting the assignment, I would be scheduled to present my findings to several members of the team. I spent 4-5 hours on the assignment, which was not overly difficult but nonetheless required dedicated effort. After submitting the project within two days, I was COMPLETELY GHOSTED / IGNORED by the hiring manager. I followed up several times by email, Linkedin, and even his personal phone number (which he shared). Nothing. No response or even acknowledgment of the time I'd put in. I understand people are busy and there may have been a more qualified candidate. But to treat applicants this way -- after they've put time and effort into an application and assignment -- is shameful. Hopefully others at CPower don't behave this way -- but I wanted to flag this for anyone who may have a similar experience.