Django login fails for some, not all

http://www.mydeliverylist.com Registration seems to be working just fine, but when users go to login with the completed registration, the webpage redirects to the开发者_开发问答 main page without actually logging in. I've verified that the database is properly updated. However, on a local network (I'm hosting), I can register and log in just fine.

Why is the login failing for some?

Sounds like the user is not accepting cookies. Either misconfiguration of their side, or there's something wrong with the domain name that the cookie is set to.