Unable To Login To Xfinity Email

Hello. I am looking for help getting my email working again. This is a lifetime email from an account that was closed years ago. I received an email stating that I need to update my password for this account. When I attempt to do so I receive an error:

"We are unable to change your password because there is not an eligible verified mobile number or email on file. You will need the Primary account holder to make the change for you. Once the primary has reset your password, please add a mobile number, or email address to your profile so we can better assist you with future password resets and troubleshooting"

I then logged in as the primary account holder and found that my email (the "secondary account') is no longer there and there is nothing I can do to fix this from my end. 

I have spoke to customer service multiple times but they don't seem to understand my issue.  This is a email that I have used for 10+ years and I was  allowed to keep it when we cancelled our service many years ago. If someone could please help me or even point me in the right direction I would really appreciate it.