"Environment"
OS = rhel 6.3
Subscription = Red Hat Enterprise Linux Developer Suite
Expire data = 2016/02/11

"Problem"
I am not able to subscribe redhat.

subscription-manager register --autosubscribe

Username: xxxxxxxx
Password: xxxxxxxx
The system has been registered with id: d1eaa18f-3d09-4bc8-b204-3e6d06305a31
Installed Product Current Status:
Product Name: Red Hat Enterprise Linux Server
Status: Not Subscribed

subscription-manager subscribe --auto

Installed Product Current Status:
Product Name: Red Hat Enterprise Linux Server
Status: Not Subscribed