And you didn't put your mobile phone number in?
7 years ago, they weren't asking for a mobile phone number.

Fair enough.
After 7 years of inactivity could it have been voided, put back into the pool and someone else now has it?
Found this:
Q. I don’t care about the contents, I just need the e-mail address back because I have other things linked to that address.
A. Account names are never re-used, so you can’t re-create the account. So to get the name back you will have to try and recover the account.
At the end of the day if you don't know the password and didn't set up any of the recovery options then you're probably SOL. How else can you prove the account was yours?