Wrong apple id in my new iphone icloud

Now and two years I have a new Apple ID with new email address for my devices. My previous email address (gmail) does NOT exist any more. Yesterday I bought a new iphone 6s. I plugged it into itunes and restore it through previous iphone 4 that I had, unfortunately with previous email address. Now I can not restore it because it is asking me the old one icloud password that does not exist any more. Could you help me please..