// Start button. private async void Button_Click(object sender, RoutedEventArgs e) { Parsing p = new Parsing(Login._instaApi); var usersList = await p.GetUserFollowers(userAddress.Text); var nonPrivateFollowers = usersList.Value.Where(x => x.IsPrivate == false).Select(x => x.UserName); using (FileStream fstream = new FileStream($@"{folderTextBox.Text}\publicFollowers.txt", FileMode.OpenOrCreate)) { using (StreamWriter swriter = new StreamWriter(fstream, Encoding.UTF8)) { foreach (var item in nonPrivateFollowers) { await swriter.WriteLineAsync(item); } } } }