Session key disappeard...

Hello, I have a strange behaviour regarding Session, When playing with Socialite, I added an email key to the session, I can see it right after adding it when I hit /social/auth/facebook/callback but when i hit /lab/session which just a dd(session()->all()) I have no email key any idea ?

public function handleProviderCallback($provider)
    {
        try {
            $user = Socialite::driver($provider)->user();
        }
        catch (\GuzzleHttp\Exception\ClientException $e) {
            return redirect('social/auth');
        }
        // storing data to our use table and logging them in
        $data = [
            'first_name' => $user->user['first_name'],
            'last_name' => $user->user['last_name'],
            'name' => $user->getName(),
            'email' => $user->getEmail(),
            'avatar'=> $user->getAvatar(),
            //'originalAvatar' => $user->getAvatar_original(),
        ];
        echo 'Socialite User :<br/>';
        var_dump($user);
        echo 'Data :<br/>';
        var_dump($data);
        $dataSerialized = serialize($data);
        echo 'Data serialized :<br/>';
        var_dump($dataSerialized);
        $dataUnSerialized = unserialize($dataSerialized);
        echo 'Data unserialized :<br/>';
        var_dump($dataUnSerialized);
        //Put the facebook user ID into Session
        session()->put('email',$user->getEmail());
        //\Session::put('email',$user->getEmail());
        echo 'Session :<br/>';
        var_dump(session()->all());
        //Auth::login(User::firstOrCreate($data));

        //after login redirecting to home page
        dd('done');
        return redirect('register');
    }