Forgot email used for registration on perpetual license

I bought Acrobat XI Standard perpetual license over 10 years, a physical disk. I just finally got a new computer after 12 years and the new computer wants me to to deactivate the license on the old computer so I can use it on the new computer.  I did deactivate it. I am trying to reactivate it on the new computer but I don’t know which email address I must have used to originally register it. I have tried all my active email accounts, but with no luck. I have reached out to Adobe and they no longer offer phone support for this product and my support via email has not been great at all with Adobe. They told me to post to this community for help. Any suggestions? Calling Adobe is useless as it states they new longer offer phone support for this product and then the phone call ends.