Unable to manage my services because of Flex: "Since Flex is in your plan, the Xfinity Assistant"

I am unable to manage my account (even look at what is offered in my area) since I added Flex. I receive this error: Since Flex is in your plan, the Xfinity Assistant can help complete your order online.

I see in the forum that a fix is being worked on, but that was back in September. I also see that this has been fixed for others manually. Can you please help me?

Thanks,