I found a solution.
"Why the hell it works for all users but 2"?
Well, they were the only with whom I have shared the folder in which I am creating the file.
It is unnecessary as they use my flow which uses my folder. By sharing... well I have no idea what happens. The solution was just enter in their OneDrive and press "unlink folder" or something like that (forget...).
Anyway it drove me crazy for a day. non-sense 😄