django does not send csrf token again after browser cookies has been cleared

I had the same problem. After debugging against django source, the reason is:

If your view is not rendering a template containing the csrf_token template tag, Django might not set the CSRF token cookie.

Two solutions:

• Add {% csrf_token %} in your template
• Use @ensure_csrf_cookie decorator for your view

For detail your can refer django doc.

Look at django/middleware/csrf.py in which CsrfViewMiddleware class is declared. As you can see in def process_response(self, request, response) there are three conditions that prevent cookie setup:

def process_response(self, request, response):
    if getattr(response, 'csrf_processing_done', False):
        return response

    # If CSRF_COOKIE is unset, then CsrfViewMiddleware.process_view was
    # never called, probaby because a request middleware returned a response
    # (for example, contrib.auth redirecting to a login page).
    if request.META.get("CSRF_COOKIE") is None:
        return response

    if not request.META.get("CSRF_COOKIE_USED", False):
        return response

    # Set the CSRF cookie even if it's already set, so we renew
    # the expiry timer.
    response.set_cookie(settings.CSRF_COOKIE_NAME,
                        request.META["CSRF_COOKIE"],
                        max_age = 60 * 60 * 24 * 7 * 52,
                        domain=settings.CSRF_COOKIE_DOMAIN,
                        path=settings.CSRF_COOKIE_PATH,
                        secure=settings.CSRF_COOKIE_SECURE
                        )
    # Content varies with the CSRF cookie, so set the Vary header.
    patch_vary_headers(response, ('Cookie',))
    response.csrf_processing_done = True
    return response

Check which is applied for you.