The same thing happened to me with scaleway, it worked for me until approximately May 16, then it didn’t work.
Additionally, believe me, I did more than 50 tests (changing all the values), and the only way that worked was if I left “s3 backup bucket” blank, and what the system did was create a folder called “default”, but It worked… Otherwise, no matter how many combinations I did, creating new AIs, modifying permissions, nothing worked.