RHEL 7.4 registration / subscription problem

I successfully installed RHEL7.4 on my first PC and for the first time am successfully subscribed, however i change the installation disk so that i format and installed again there happened the subscription manager display "No service level will cover all installed products. please manually subscribe using multiple service levels via "All available subscription tab or purchase additional subscriptions. I'm failing with subscribing after registering (and even forcing a registration) as follows:
[root@dhcppc9 ~]# subscription-manager register --username xxxx --password xxxxt --auto-attach --force
The system with UUID ba9f5742-4c4d-9c72-e42c34f02fd4 has been unregistered
Registering to: subscription.rhsm.redhat.com:443/subscription
The system has been registered with ID:7e8dbad6-0538-449d-a626-2f9c37dfd86e

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

Unable to find available subscriptions for all your installed products.
[root@dhcppc9 ~]# subscription-manager list --available --all

No available subscription pools to list

Any help much appreciated.