file_copy() does not work [closed]

Question

I have the following code.

$main_image = glob('main*.{jpeg,gif,png,jpg,JPEG,JPG,PNG}', GLOB_BRACE);
if (count($main_image) != 1) {
  die("Could not find main picture !");  
    
  $file_path = drupal_realpath($main_image[0]);
  $file = (object) array(
    'uid' => $userID,
    'uri' => $file_path,
    'filemime' => file_get_mimetype($file_path),
    'display' => 1,
    'filename' => $main_image[0],
  );

  $destination = "public://galerii_imagini/" . $file->filename;

  if ($file = file_copy($file, $destination, FILE_EXISTS_REPLACE)) {}
  else {
    die("Could not copy " . $file_path . " in " . $destination);
  }
}

In the Drupal logs, the error message is the following.

File ..../main_ROSE2106.JPG could not be copied, because the destination directory public://galerii_imagini is not configured correctly.

What should I do to configure it correctly?
In /admin/config/media/file-system I set the the path for public files (sites/default/files) and set the file permissions for that directory recursively to 777.