iPhone Activation Lock

My brother couldn't get verification on his iphone to turn off find my iphone which he put on it over a year ago so he reset it back to factory settings, now it is asking for his apple id and password but he can't remember the password or the security questions what can we do?

We have tried to log in to the email address that he set up with but it's not found :/ I think maybe he didn't verify it when he set up the account. I am a little stuck and am just hoping someone may be able to help me with this issue?

Thanks