The information you have provided is too general to determine the best troubleshooting path.
You would need to verfiy enforcer connectivity to the manager
You would need to check the agent profile settings
You would need to verify the DHCP production and quarantine scope settings set in the managment console are correct
The fontline team for SNAC should be able to walk you through configuration issues. If you can focus your question a bit more, we might be able to help you here on the forums.