Email password change blocked

We have a similar situation as others have posted in being unable to change the password for an old Xfinity email address used by a family member in my home that is/was attached to an account that was closed 7 years ago following the death of my elderly mother.  Multiple calls made, hours spent trying to speak with a human but NO humans to speak with, disconnected calls and misinformation. Nothing but frustration,  frustration, frustration with this problem caused by this terrible company who didn't care about the nightmare they had to know would result. After five days of no email and finally getting someone to say it was a system problem they were working to resolve, the email mysteriously returned. Now another five days later, back again to the same issue of being unable to change the password and access email. Again....ABSOLUTELY NO ONE AVAILABLE TO HELP, hours and hours on the phone.... no response,  no resolution. We are referred to as a "Diamond Member" - and seriously Xfinity,  your company and its services are the absolute worst! Please someone,  provide an answer to this company created nightmare.