FSB Technology interview questions

30 mins interview, asking about my general experience mainly on the programming languages Ive have used in education and in the workplace. With mentions of neural nets, tensor flows and programming for business purposes

there were few stages to it, initial technical chat with curent Lead Developer who was promoted and was looking for replacement for his position, then it was completing code challange that took about 3 full working days to complete (instead of 4 hours that it meant to be, i am not slow it was just big task). I felt that I was perfect fit for the role as most of my career I have worked in gambling sector and I am also familiar with all technologies listed in requirements. Final stage was chat with CTO and current Lead Developer. Feedback after final stage of the interview was somehow delayed and very weak. Recruiter also said that he cant understand why I was declined. All stages went really well in my view. Somehow someone made decision to decline and the main reason was that apprently I do not want it enough.