Yii Framework $ model-> save（）仅适用于一个模型

I try to take the facebook information of a user in my databade. I'm in the UserIdentity to control the athentification of the user and i created this method.

<?php
public function insertFbUser()
{
    $user = new User();
        $user->fbId = $this->username['id'];
        $user->username = $this->username['username'];
        $user->email = $this->username['email'];
        $user->password = $this->password;

    $profile = new Profile();
        $profile->first_name = $this->username['first_name'];
        $profile->last_name = $this->username['last_name'];
        $profile->birthday = strtotime($this->username['birthday']);
        $profile->sex = $this->username['gender'];
        $profile->fb_updated_time = strtotime($this->username['updated_time']);
        $profile->fb_verified = $this->username['verified'];
        $profile->fb_educationJson = json_encode($this->username['education']);
        $profile->fb_workJson = json_encode($this->username['work']);

    var_dump($user->save());
    var_dump($profile->save());
}

the var_dump() show me this

boolean true
boolean false

Both models were created with the GII module. I try to only put one prile attribute at a time and it doesn't work too...

There is my DB : http://pastebin.com/u5CNKj9M

Thank you for your help!

print_r($profile->getErrors());

(Update)To get user id after saving:

$user->save();
$user_id = $user->id