How to create and write a text file after compile/build

I've been struggling with this for quite some time now and I've already posted a few questions but didn't get the answer I was looking for, and that's probably because I didn't ask the question correctly.

I'm trying to store some gamedata in a text file and it all works fine when I'm testing it in the editor but as soon as I try to do it after building nothing happens, no files are created and no text is written. This is what I'm doing :

         FileInfo f = new FileInfo(Path.Combine(Application.persistentDataPath, "data.txt"));
         StreamWriter w;
         if(!f.Exists)
         {
             w = f.CreateText();
         }
         else
         {
             f.Delete();
             w = f.CreateText();
         }
 
         foreach (string s in text)
         {
             w.WriteLine(s);
         }
         w.Flush();
         w.Close();

Now 's' is a List that contains the data I want to write to the file. I've tried working with a TextAsset too but I haven't gotten that to work either after building the game.