When might one expect a reply to the email? There are at least 2 of us in our organization with the same looping login issue. This is pretty frustrating as most people are having no issues.
Thanks Jesse, there is also a live chat bubble bottom right on the UC website here - please try that. I'll update the response above to indicate this option:
This was never resolved and there are 3 people in my org who have the same issue. I went through the support chat twice. The first time they told me that my registration had been "updated" (whatever that means) and to wait 5 minutes and log in. After 15 minutes it still wasn't working so I went back to the chat. This time I received some generic log out, clear cache, try different browser, type advice which did not work. Then I was told that my information was being sent to support. I was told they would be in contact with me via email "if necessary."
UPDATE: there are now 4 people affected in my org.
Please refer to this response from our Esri team regarding issues experienced and avenues of support:
Re: stuck in redirect loop, unable to register for... - Esri Community