Sertifi interview questions

Interviewed with Sertifi and went through the entire process. Which involved interviewing with 6 people… was later told after 3 weeks from finishing the last interview that they had decided to still keep interviewing more candidates. And that they felt that I wasn’t able to answer some of their questions to their satisfaction because I stated I had an NDA. Which I do so I obviously can’t go into certain topics and that should be obviously clear to any professional in any industry. I Decided to pull my candidacy in the end since if they can’t even get interviewing right then what kind of team and working conditions would I walking into.