Yahoo account login

Hello,
My phone is connected to my old yahoo email, I tried signing in because I remember the password. When I tried to sign in it said for security reasons we need to verify that it's me, but the email they send it to is an email I have never seen before. In order to unlock my phone I need to get on this email and I cannot figure out how to get on it because the email they use for me to verify is not mine and I've never seen it before. I've tried everything to get in my email but nothing has worked. Someone please help.