my boyfriend borrowed my Iphone and changed my account by changed email and password. Also he created mail of icloud that is not my email. Now I've turned my Iphone. So I try to change mail account of icloud but it's still his account's icloud. Help me!

my boyfriend borrowed my Iphone and changed my account Apple ID by changed email and password to be his informations. Also he created mail account of icloud that is not my email. Now I've turned my Iphone. So I try to change mail account of icloud to be my mail but it's still his account's icloud. What should I do on this occer???

Sometimes I think that I want to create the new Apple ID by the same email but I cannot do that.

Help Me!!