Steper 2 says Invalid file when is uploaded to heroku

[rafaelsanchezrd]

Describe the bug
In the next screenshoots you could see that loading the stepper is being done in the same way that the select2 is being loaded but I get this error, when I upload the application to heroku.

CodeIgniter\View\Exceptions\ViewException
Invalid file: agungsugiarto\boilerplate\Views\load\steper.php

the view calling this file has this:
<?= $this->include('agungsugiarto\boilerplate\Views\load\steper') ?>

and the content of the file is just this:
<?= $this->section('css');?>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bs-stepper/dist/css/bs-stepper.min.css">
<?= $this->endSection();?>

<?= $this->section('js');?>
<script src="https://cdn.jsdelivr.net/npm/bs-stepper/dist/js/bs-stepper.min.js"></script>
<?= $this->endSection();?>

To Reproduce
Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots

Additional context
Add any other context about the problem here.