Access Denied for programmatically added file to a node

I have a custom script that imports contents from an external database. I'm attaching files using the below custom code.

$file = File::create([
  'filename' => $new_filename,
  'uri' => $folder_uri . '/' . $new_filename,// private://my_content_type/<subdir>/filename.pdf
]);
$file->setPermanent();
$file->save();

Once the above part is complete, then attach that file(s) to the new node using the below custom code.

$storage_handler = \Drupal::entityTypeManager()->getStorage("node");
$data = [
    'type' => 'my_content_type',
    'title' => 'A title',
    'status' => 1,
    ...
    'field_attach' => ['target_id' => $file->fid->value],
    ...
  ];
$node = $storage_handler->create($data);
$node->save();

When I edit the same node I see the correct file attached but while opening it in preview, I receive "Access Denied", even I'm logged as an admin.

Though, the field field_attach is a multiple one and if I manually attach another file from the edit page and save it, then I can correctly preview it.

debug:

This is the devel part for the node:

[field_attach] => Array
(
    [x-default] => Array
    (
        [0] => Array
        (
            [target_id] => 1876 // Can't preview, access denied
            [display] => 1
            [description] => 
        )
        [1] => Array
        (
            [target_id] => 1878 // Can preview it
            [display] => 1
            [description] => 
        )
    )
)

In database each file has same values:

# select * from file_usage where fid in(1876, 1878)\G
*************************** 1. row ***************************
   fid: 1876
module: file
  type: node
    id: 92
 count: 1
*************************** 2. row ***************************
   fid: 1878
module: file
  type: node
    id: 92
 count: 1
2 rows in set (0.000 sec)


# select * from file_managed where fid in(1876, 1878)\G
*************************** 1. row ***************************
     fid: 1876
    uuid: 876c1bd1-566c-4d6b-a767-4925d75b593f
langcode: it
     uid: 1
filename: first_file.pdf
     uri: private://my_content_type/201211/first_file.pdf
filemime: application/pdf
filesize: 140982
  status: 1
 created: 1651744379
 changed: 1651744379
*************************** 2. row ***************************
     fid: 1878
    uuid: 4c26c169-3e92-4254-af49-e5b203caf4c6
langcode: it
     uid: 1
filename: second_file.pdf
     uri: private://my_content_type/202205/first_file.pdf
filemime: application/pdf
filesize: 140982
  status: 1
 created: 1651745721
 changed: 1651745725
2 rows in set (0.000 sec)

Permissions are the same for directories and for files. Something is different from manual and programmatically attach. Lost to set something?

Thanks in advance.

Your code looks OK to me. However, not sure what file permission you want. Have you tried passing user id to see whether you are able to see the uploaded file?

  $file = File::create([
      'filename' => $new_filename,
      'uri' => $folder_uri . '/' . $new_filename,
      'uid' => 1,
    ]);

Just a recommendation, it would be ideal to pass the file id using id() function.

 'target_id' => $file->id(),