Ya, this is hard. I bombed an Amazon interview because the interviewer asked me Alien Dictionary, a well known LeetCode problem that I already worked out while practicing. I told her outright that this was a problem everyone practiced, but she still dinged me for already knowing the answer and not going through the “figure this out flow” (admittedly, I could have handled that better, but it is actually difficult to work through something that you know the answer to but forgot how you got the answer).
At least it was for a job I probably wouldn’t have taken.