rest api register with myth auth

public function create()
    {
        // http://localhost:8080/api/v1/users
        // parameter yang harus diisi: (method post)
        // {
        //     "username": "The username field is required.",
        //     "email": "The email field is required.",
        //     "password": "The password field is required.",
        //     "pass_confirm": "The pass_confirm field is required.",
        //     "fullname": "The fullname field is required.",
        //     "phone": "The phone field is required.",
        //     "nik": "The nik field is required."
        // }

        // Check if registration is allowed
        if (!$this->config->allowRegistration)
        {
            return $this->respond(lang('Auth.registerDisabled') ?? $this->failServerError());
        }

        $users = model(UserModel::class);
        // Validate here first, since some things,
        // like the password, can only be validated properly here.
        $rules = [
            'username'      => "required|alpha_numeric_space|min_length[3]|is_unique[users.username]",
            'email'         => "required|valid_email|is_unique[users.email]",
            'password'      => "required|strong_password",
            'pass_confirm'  => "required|matches[password]",
            //tambahan
            // 'fullname'      => "required|max_length[255]",
            // 'phone'         => 'required|max_length[15]',
            // 'nik'           => 'required|numeric|max_length[255]',
        ];

        //jika validasi error
        if (!$this->validate($rules))
        {
            return $this->respond($this->validator->getErrors());
        }

        // Save the user
        $allowedPostFields = array_merge(['avatar','password','fullname','phone','nik'], $this->config->validFields, $this->config->personalFields);
        $data = $this->request->getPost($allowedPostFields);

        // print_r($data);
        // die;

        $user = new User($data);

        $this->config->requireActivation !== false ? $user->generateActivateHash() : $user->activate();

        // Ensure default group gets assigned if set
        if (!empty($this->config->defaultUserGroup)) {
            $users = $users->withGroup($this->config->defaultUserGroup);
        }

        //jika user gagal register
        if (!$users->save($user))
        {
            return $this->respond($users->errors());
        }

        if ($this->config->requireActivation !== false)
        {
            $activator = service('activator');
            $sent = $activator->send($user);

            if (!$sent)
            {
                return $this->respond($activator->error() ?? lang('Auth.unknownError'));
            }

            // jika aktifasi diaktifkan maka wajib cek email
            $aktifasi = [
                'status' => 200,
                'success' => TRUE,
                'message' => 'registrasi selesai, silahkan cek email anda untuk verifikasi'
            ];

            return $this->respond($aktifasi);
        }

        $get_user = $this->modelUser->where('username', $user->username)->first();

        // untuk simpan setting default
        $setting_entity = new SettingNotifEntity();
        $setting_entity->id_penyewa = $get_user->id;
        $setting_entity->reminder_pembayaran = 7;
        $this->setting->save($setting_entity);

        //print_r($user);

        // Register benar benar Success!
        return $this->respond($get_user);
    }