Issue accessing email or anything.

For years this account has been my primary email until a couple years ago when the linked email got sent a message of termination for my comcast email due to unpaid bills. My grandmother cant pay bills while she is deceased but this also seems to have broken the email I was using (her grandchild, she payed for internet so i could take online classess). is there any possible way to at least reinstate the email if nothing else so i can get some important things linked to my current new email?

For some context if i try to access my emails or anything with this account it always defaults back to xfinity.com/auth I was honestly surprised i was even able to access this to make the post. (its also labeling me as user_fyzfpt in this post rather than my grandmothers name)