Noom Sr. Software Engineer interview questions

The coding interview was really chaotic. The interviewer forgot to mention an important part of the problem to fix it at first, so I had to rewrite part of the solution in the last few minutes. After finishing the test, I explained that this is not the most efficient solution to the problem and explained why. I also explained that I decided to build this solution only because they changed the problem in the last few minutes, so I went to something easy. When I asked for feedback on the code interview, I never got an answer.

First time applied in October 2020, received an automatic message to provide my availability. On the day of interview the recruiter didn't call. Nor he replied to my followup email. Second time I was contacted by a Noom's Co-founder, saying that they are still looking for developers - we organized the phone interview with the same recruiter and (surprise!) - he didn't call again. I totally understand that sometimes some unexpected things happen, but you still have to be professional and respect the time of other people - how hard is it to write a one-liner email, saying that you won't be able to call?