Changing Xfinity forum email address

Hi,

I have changed my email address and would like to update the email address used with the Xfinity forums. I found some pre-existing posts about this, such as https://forums.xfinity.com/conversations/getting-started/update-email-address-for-community-forum-account/64ea734fde75d267de828811

According to that and other posts, I should update my email address on the main Xfinity web site, which I have already done. The main Xfinity web site appears to have no record of my old email address, and when I attempt to login to the main web site with my old email address, I correctly get the error "The Xfinity ID you entered was incorrect. Please try again."

However, if I login to the Xfinity forums, using my correct email address and password, it automatically brings up my old email address on the forum site. Other forum posts talk about re-registering, but I have not encountered any possibility of re-registering, because logging in with my new email address automatically brings me to the pre-existing forum account with my old email address.

How can I update the email address on my old forum account (which I understand to not be possible), or actually re-register with a new forum account with the new email address that is already on my Xfinity account?

Thanks!