If you need to modify the details of an API-Portal that is already unregistered from CentraSite, you must modify it in CentraSite and then republish (reregister) it with CentraSite. If you make changes to the endpoint of an API-Portal, for example, you must update the details page of the API-Portal with the new API-Portal's configuration, reregister the API-Portal with CentraSite to put those changes into effect.