Django deployed app shows following error: "Refused to execute script from "url/file.js" because its MIME type"

I followed this deployment tutorial https://docs.digitalocean.com/tutorials/app-deploy-django-app/ and after trying to add staticfiles I get the title’s error. This is the static configuration:

STATIC_URL = 'staticfiles/' # I changed this from 'static' because I tought it could work but it didn't.
# STATIC_URL = "/static/"
# Add these new lines
STATICFILES_DIRS = (
    os.path.join(BASE_DIR, 'static'),
)

STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')

This is how the file is requested on django template:

{% load static %}
<script src="{% static 'appointment-scripts.js' %}"></script>

And this is how it is rendered by browser:

<script src="/staticfiles/appointment-scripts.js"></script>

In my directory the file “appointment-scripts.js” exists so I think that the problem is some configuration on my app, but I just don’t know how to get more information about this, any help would be appreciated.