Thanks for using JustAnswer. This is Leela and I will help you with the question today.
If you donot know the answers to security questions then you wont be able to LOGIN to your account unless you get the phone number in order to do phone verification.
I guess the other person should have changed the 2 step verification process when your phone was active.
I am afraid you may loose access to the account if you donot have anyway to RECOVER the account as you wont know the password.
What's the email address?