Cant access legacy att.net email account

I have forgotten my password, when I try and reset it I am prompted to answer security questions which I don't believe I ever set up.  I have had this email for about 15 years and have moved and changed phone numbers several times.  So I do not remember which telephone number or zip code might have been associated with my email if any at all.  I don't even recall using at&t service for anything other than email.  I access my email via yahoo.com.  Something odd to note is I can still see the last emails I received on my tablet which was back on June 29th 2020.  I am hoping this will find the right person that can assist in resetting my password and or unlocking my account.  Seems like this might be near impossible to get to the correct person being there is NO option related to email/login issues.