activation issue

while iam registering by hitting commands like • sudo subscription-manager register from Rhel os environment,it is not allowing me to add my subscription which is already activated of no-cost subscription instead it thrown the errors as following, error:
HTTP error (401 - Unauthorized): You must first accept Red Hat's Terms and conditions. Please visit https://www.redhat.com/wapps/tnc/ackrequired?site=candlepin&event=signOn . You may have to log out of and back into the Customer Portal in order to see the terms.
after entering into below link,
link to https://www.redhat.com/wapps/tnc/ackrequired?site=candlepin&event=signOn.
it is again throwing an error as following,

Something went wrong. If the problem persists, please Contact Customer Service.