Auth Failure in Form

Auth Failure in Form

Rails has generated this action url for my form:
<form action="/auth/failure?action=update&controller=users"...
I'm authenticated to the website, even If I shouldn't be, it would
redirect somewhere as I understand Auth.
My Form code:
<%= form_for @user, :url => { 'controller' => 'users', 'action' =>
'update'} do |f| %>
Thanks!