Форма PHP не создает файл .csv

Это успешно работает

<?php
if (isset($_POST["submit"])){

  $data = array();

  $data['name'] = $_POST["name"] ?? '';
  $data['email'] = $_POST["email"] ?? '';
  $data['customer'] = $_POST["customer"] ?? '';
  $data['reseller'] = $_POST["reseller"] ?? '';
  $data['standardusers'] = $_POST["standardusers"] ?? '';
  $data['ucusers'] = $_POST["ucusers"] ?? '';
  $data['recording'] = $_POST["recording"] ?? '';
  $data['firewall'] = $_POST["firewall"] ?? '';

  $errors = '';

  foreach ($data as $key => $value) {
    if ($key == 'recording' || $key == 'firewall'){ } //do nothing
    else {
      if (empty($value)) {
        //Field is empty && email
        if ($key == 'email') {
          if (!filter_var($data['email'], FILTER_VALIDATE_EMAIL)){
            $errors .= 'Please enter a valid email address \r\n ';
          }
        } else {
          //Field is empty && !email
          $errors .= $key.' field is required. \r\n ';
        }
      }
    }
  }

  //if no errors carry on
  if (empty($errors)){
    //# Title of the CSV
    $Content = "Name, Email, Customer, Reseller, Standard Users, UC Users, Call Recording, Firewall\n";
    //set the data of the CSV
    // Added '' in each field as a delimiter
    // $Content .= "'".$data['name']."', '".$data['email']."', '".$data['customer']."', '".$data['reseller']."', '".$data['standardusers']."', '".$data['ucusers']."', '".$data['recording']."', '".$data['firewall']."'\n";
    $row = '';

    foreach ($data as $key => $value){
      $row .= $value.","; //Append data to csv
    }
    //Remove trailing comma
    $row = mb_substr($row, 0, -1);

    $Content .= $row;
    //# set the file name and create CSV file
    // $filename = "formdata-".date("d-m-y-h:i:s").".csv";
    // header('Content-Type: application/csv');
    // header('Content-Disposition: attachment; filename = "'.$FileName.'";');
    // echo $Content;
    // echo gethostname();
    // exit();

    $csv_handler = fopen ('csvfile.csv','w');
    if (fwrite ($csv_handler,$Content)){
      echo 'Data saved to csvfile.csv';
    } else {
      echo "File not saved successfully";
    }
    fclose ($csv_handler);


  } else {
    echo $errors;
  }

}


?>

Я тестировал с помощью этой формы, отправляя в скрипт

<form class = "" action = "3.php" method = "post">
  <input type = "text" name = "name" placeholder = "name" >
  <input type = "text" name = "email" placeholder = "email" >
  <input type = "text" name = "customer" placeholder = "customer" >
  <input type = "text" name = "reseller" placeholder = "reseller" >
  <input type = "text" name = "standardusers" placeholder = "standardusers" >
  <input type = "text" name = "ucusers" placeholder = "ucusers" >
  <input type = "text" name = "recording" placeholder = "recording" >
  <input type = "text" name = "firewall" placeholder = "firewall" >
  <input type = "submit" name = "submit" value = "submit">
</form>