Crossover for Work C# (.NET) Software Engineer - Tournament Testing interview questions

Firstly, they start with online test, I passed it. after that they said that's tournament so you can skip project part ok. We arranged an tecnical interview, question was easy but a little tricky. Well I passed this stage as well, The interviewer guys asked to me experience, etc. and also he said hr team will make an interview with you next week, I said ok . Today they sent me e-mail and I failed lol. There is no any feedback which part I failed I do not know? I guess this company, is not fair.