Kantar Data Scientist interview questions

First interview with HR. Second interview with Head of Data to understand my goals and what did I wanted to do. Third interview was a discussion of a challenge that they gave me to do in 1 week. They were really fast and helpful answering my calls and question during this period. After the third interview they took almost 1 month to give me any answer about if I would get in or not.

HR call, Technical interview, Take home task Had a call with recruiter who seemed impressed with my application and assured that they will set up the next interview. Never heard anything, have messaged twice and ghosted. Very unprofessional.