Stripe Applications Security Engineer interview questions

First there was a CV screening where I was selected and I was explained on the process There shall be Coding exercise followed by Security interview by global security head in U.S after that there will be an CTF kind of exercise later meeting the team / manager for final round I spent 35 to 40 mins or so delivering functioning Python - I have a computer science degree and I have worked in security for several years. Whilst coding is not my number one requirement at the moment , I consider myself a proficient coder. However, I was surprised to find that, despite my code being entirely functional and delivering on all objectives, I was told I was not selected. That's fine, but frustratingly there was no constructive feedback - just "you were not selected ". I can only assume that they were not looking for a script, but something that could be deployed; a strange task given that security engineers aren't really writing code for deployment, but scripts for task automation, etc. Was not really happy with the outcome but nothing we can do right.