PXL Vision interview questions

1) Short call with HR 2) Call with hiring manager 3) Case study I had rather standard interview questions, except that the contact of the reference person was asked on the second interview. This was a bit strange, because it wasn't clear yet, whether they would select me. Everything went fine until the final interview, where I was asked to prepare a presentation. As of course, I was interested in working for the company I invested quite some time in preparation. An HR has called me to inform about rejection. The person however couldn't provide any feedback on the reasons and what could be improved. Although I asked for it right after in writing, I had no response since then. I found this rather unprofessional. I do believe, that giving feedback should be a standard, once the interviewee reaches the final round.