Apinity interview questions

I had the first call with The HR manager which was short, friendly and he scheduled the next interview right away during the call, the next interview was with 2 developers, which was also quite deep technical discussion, next day I received inviation for the next technical interview with the VP of Engineering and a Senior Developer, which was also technical but a bit high level, my assumption was it was good as well from both sides, but 2 days later I received a rejection email wtihout stating any details. Feedback: - Provide feeback to candidates about what didnt go well. - Having one longer technical interview instead of 2.