Solved! Go to Solution.
Hi @Jharman2012, can you go here https://customer.xfinity.com/#/settings/account/linked-accounts and unlink your old account ending in "6" and see if you can sign in again? We're looking into the issue with our developers.
Thanks for your patience, and enjoy your services! There's already guidance with our XM Care teams around this as a first diagnostic step, we'll add this to the pinned issue too. It's a high-priority item for fixing.