Problem when Upload file any connection is established

[Keopss]

Hi team! I need help when I try to upload files from a post.

I have this code inside a "for" bucle:

for ($i = 0; $i < count($_FILES['pictures']['name']); $i++){
$path_parts = pathinfo($_FILES['pictures']['name'][$i]);
$image_path = $path_parts['filename'].$path_parts['extension'];

      $uri =  $image_path;
      $file = $_FILES['pictures']['tmp_name'][$i];
      $input = S3::inputFile($file);
      if (S3::putObject($input, $bucket, $uri, S3::ACL_PUBLIC_READ)) {
        echo "File uploaded.";
        } else {
            echo "Failed to upload file." . $uri . $bucket . $input;
        }
    }

But not works. I have configured my keys but I think that the problems comes maybe to not set region of the bucle?

Please any help is appreciated. Thank you!