[Fixed]-Setting flat pages in admin model

You have configured the pages URLs with a prefix of ^pages/, which means you need to add that prefix to your request URL. E.g., for a page that you have configured as /help/overview/, you would access it from http://localhost:8000/pages/help/overview/.

You either need to request all your page URLs with a /pages/ prefix, or use one of the other methods described in the documentation:

You can also set it up as a “catchall” pattern. In this case, it is important to place the pattern at the end of the other urlpatterns:

from django.contrib.flatpages import views

# Your other patterns here
urlpatterns += [
    url(r'^(?P<url>.*/)$', views.flatpage),
]

Another common setup is to use flat pages for a limited set of known pages and to hard code the urls, so you can reference them with the url template tag:

urlpatterns += [
    url(r'^about-us/$', views.flatpage, {'url': '/about-us/'}, name='about'),
    url(r'^license/$', views.flatpage, {'url': '/license/'}, name='license'),
]

Finally you can also use the FlatPageFallbackMiddleware.