https://bugzilla.redhat.com/show_bug.cgi?id=1953340
--- Comment #13 from Ankur Sinha (FranciscoD) sanjay.ankur@gmail.com --- Infrastructure is currently seeing intermittent issues with the Fedora Open ID server.
See https://status.fedoraproject.org/ and https://pagure.io/fedora-infrastructure/issue/9990
Someone has reported: "Clearing the local storage and cookies, seems to fix the problem most of the times.", try that and see if it works?