Genmed interview questions

I attended a fist stage telephone call with the Sales Manager. What was really disappointing and unprofessional to me is that following the interview I didn’t receive any further acknowledgment from the interviewer. I chased them up on LinkedIn and they did not respond. I find this really unprofessional as people take time out of their day to attend interviews and if somebody isn’t the right fit you should provide feedback or at least let them know that they won’t be continuing in the interview process rather than never contact them.