I had a pleasant call from the recruiter talking about the fast-growing company and its good benefits. I was set up with a call for a 1hr interview. During the 1hr interview, I was asked a straightforward question and described the process out loud. There were a couple of places where I would get stuck and the interviewer would gently nudge me in a direction without telling me the answer. I was able to finish the problem and state the time and space complexity. The rest of the time I had a pleasant chat about the company and its future. I got an email a day later saying that they decided not to move forward this time. I asked the recruiter for any feedback at all, and they couldn't give me any. I'm disappointed with the outcome because I'm not really sure what I did wrong. Maybe I had to be perfect during the tech screen? I'm not sure.