For client-based log-ins, you can also use your account title. (the name you have given that particular account)
in combination with the password. When it comes to help for these kinds of issues, it is best to reach out to staff.
You can try support requests, which will be answered in due time by an active member of the staff team.
However, before any staff member can be of help, you do need to know the original email-address that is linked to that account.
If you really cannot remember the original email-address, you can try redirecting the details to another email address, and then validate said email-address.
If I were you, I'd try re-connecting a more current email-address to the account, and if possible, update the password.
(and write it down, since you tend to forget, I've gathered) If this fails, give SR a chance.
I hope you manage to recover the account!