Can't transfer file from datapath to devices

Hi, I have a following piece of code to save game configs which are retrieved from Google spreadsheets. This piece works in the editor! I just press a button like "Sync with google" and it downloads new data, then I want to have a build with that data, not retrieving it from actual aplication on mobile. There is also a bulk which initializes content with the Load function, but nothing special aboiut it. Everything works fine in Unity when I press play, until I begin to build my project for iOS or Android, DoesSaveExist(string name) function on device returns false, so building doesn't properly handle .dataPath saved files. I also tried using .persistentDataPath but it is located somewhere at users/application data on PC so I have no idea how it may be included in the build. Also tried storing in Assets folder, but still not working. Please, point if I am missing something about this?

     public static string GetSavePath(string name)
     {
         return Path.Combine(Application.dataPath, name + ".sav");
     }
 
     public static bool DoesSaveExist(string name)
     {
         return File.Exists(GetSavePath(name));
     }
 
     public static bool SaveGoogleData(List<Game.Design.Level> parsedData)
     {
         BinaryFormatter formatter = new BinaryFormatter();
 
         using (FileStream stream = new FileStream(GetSavePath("GoogleParsedData"), FileMode.Create))
         {
             try
             {
                 formatter.Serialize(stream, parsedData);
             }
             catch (Exception)
             {
                 Debug.Log("Google data NOT SAVED");
                 return false;
             }
         }
         Debug.Log("Google data saved to: " + GetSavePath("GoogleParsedData").ToString());
         return true;
     }
 
     public static List<Game.Design.Level> LoadGoogleData(string name = "GoogleParsedData")
     {
         if (!DoesSaveExist(name))
         {
             Debug.Log("Google data save DOES NOT EXIST");
             return null;
         }
 
         BinaryFormatter formatter = new BinaryFormatter();
 
         using (FileStream stream = new FileStream(GetSavePath(name), FileMode.Open))
         {
             try
             {
                 return (List<Game.Design.Level>)formatter.Deserialize(stream);
             }
             catch (Exception)
             {
                 return null;
             }
         }
     }