Indeed Research Engineer II interview questions

Received an email and message on LinkedIn from the recruiter, that set up an phone interview with the recruiter. That conversation went well, the recruiter did a good job and selling the position and building me up for the interview. I asked for a couple of week to study an prepare for the technical interview and was given to me no problem. The technical interview was an hour, first part was a product interview, asking about the main indeed website and features that are available on it. I received questions about data driven decision making, in regards to the construction of indeed main website. The technical interview was not as bad as I thought, but it was still challenging for me. I was able to code out a non optimal solution, with a few hints from the interviewer. I kind of knew that I would not get an offer, based on the technical portion of the interview. First communication I received a few days later, was a survey about my interview experience. Which signaled to me, that I had been rejected, but no one told me about it. It took over a week for them to send me a autogenerated rejection email that is also an advertisement to use indeed products for my job search. I understand why, but Indeed does not give detailed feedback of your interview. It unfortunate, the time and energy I put in to prepare, all you get back is an advertisement that does not help you grow in your career. Looking around at other interview reviews, if you did well, expect to hear back right away. If not, just move on.

The interview process had an initial screening round which is an hour video interview call. They asked one easy-medium Data structure problem and some case study to test our understanding on some metrics and our though process. After I successfully completed this, I had a final interview that had around 4 rounds . The final interview in my view seemed to have went well as, I pretty much answered all questions but, any how I didn't get selected. The issue that I had with this interview is that the role I was first contacted to be interviewed for is a Product Developer role. I got an email from Indeed after four days of the final interview saying that I have not been selected for Research Engineer Level II role. I wish I had a better understanding from them on the role and their expectation because this is really confusing. I emailed the HR as well for this clarification, but they never replied back which I see as a negative here. I feel that they owe me an explanation on this confusion regarding the role as I'm left out thinking what might have happened back there. When I am spending this amount of time on getting interviewed, I would at least like to know why this confusion happened in the first place.