DigitalOcean Django Rest Framework Authentication credentials were not provided

My live site decided to throw a 403 Forbidden error yesterday on authenticated users when calling an Ajax API and I’ve been trying to troubleshoot with no success. The localhost on my machine works fine when DEBUG = True in my settings.py, but the same code throws the following error:

HTTP 403 Forbidden
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "detail": "Authentication credentials were not provided."
}

My rest framework setting in settings.py:

## REST framework default permissions
REST_FRAMEWORK = {
    'DEFAULT_PERMISSION_CLASSES': [
        'rest_framework.permissions.IsAuthenticated',
    ]
}

Since the browsable API requires SessionAuthentication, I tried the following with no success:

## REST framework default permissions
REST_FRAMEWORK = {
    'DEFAULT_AUTHENTICATION_CLASSES': (
       'rest_framework.authentication.SessionAuthentication',
    ),
    'DEFAULT_PERMISSION_CLASSES': [
        'rest_framework.permissions.IsAuthenticated',
    ]
}

I did look at Django Rest Framework Docs and it seems to suggest that if my user is logged in, the Ajax calls after login should work fine. Am I missing something? Really appreciate your input.

Update 1:

When I run the command:

sudo journalctl -u gunicorn -n 25 One of the things I see is gunicorn[820]: Session data corrupted

I did restart the server, hoping that by logging back in, the new session data will be generated, but the same message is displayed. The logged in user is still not able to view the data the ajax call is trying to fetch. How do I resolve the sessions data corrupted message. I am guessing this affects the DRF authenticating the request