Django: Сбой ограничения UNIQUE: users_customuser.email

я продолжаю получать эту ошибку, когда я пытаюсь зарегистрироваться во второй раз я пробовал несколько возможных решений, но я продолжаю получать это в любом случае любая помощь?

IntegrityError at /registration/transporteur

Вот мой код: здесь я пытаюсь иметь несколько типов пользователей

models.py

class CustomUser(AbstractBaseUser, PermissionsMixin):
    username = models.CharField(max_length= 15, )
    first_name = models.CharField(max_length= 15)
    last_name = models.CharField(max_length= 15)
    email = models.EmailField(_('email address'),unique= True,)
    phone_number = models.CharField(max_length= 15)
    address = models.CharField(verbose_name = "Address", max_length= 50, null = True, blank= True)
    # profile_picture = models.ImageField(null = True)
    # longitude = models.CharField(verbose_name = "Longitude", max_length= 100, null = True, blank= True)
    # lagitude = models.CharField(verbose_name = "Lagitude", max_length= 100, null = True, blank= True)

    date_joined = models.DateTimeField(auto_now_add=True)
    last_login = models.DateTimeField(auto_now=True)
    is_transporteur = models.BooleanField(default= False)
    is_client = models.BooleanField(default= False) 
    is_staff = models.BooleanField(default= False)
    is_superuser = models.BooleanField(default= False)
    is_active = models.BooleanField(default= False)

    USERNAME_FIELD = "email"
    REQUIRED_FIELDS = ["first_name", "last_name", "username",  "phone_number", "address"]
    objects = CustomUserManager()

    def __str__(self):
        return self.username
    def has_perm(self, perm: str, obj: None):
        return self.is_admin
    def has_module_perms(self, app_label):
        return True


class Trasporteur(CustomUser):
    user = models.ForeignKey(CustomUser, on_delete=models.CASCADE, related_name="trasporteur_account")
    matricule = models.CharField(max_length = 20, blank=True, null=True)
    car_type = models.CharField(max_length = 20, choices = CAR_tYPES)
    rating = models.IntegerField(blank=True, null = True)
    current_location = models.CharField(max_length = 20, blank=True, null=True)
    is_on_travail = models.BooleanField(default=False)
    bio = models.TextField()
    # last_transports = models.ManyToManyField('transport_services.TrasportService', on_delete=models.CASCADE, related_name="trasporteur_transports")

    def __str__(self):
        return self.user.username

class Client(CustomUser):
    user = models.ForeignKey(CustomUser, on_delete=models.CASCADE, related_name="client_account")
    current_location = models.CharField(max_length = 20, blank=True, null=True)
    # last_transports = models.ManyToManyField('transport_services.TrasportService', on_delete=models.CASCADE, related_name="client_transports")

    def __str__(self):
        return self.user.username

managers.py

class CustomUserManager(BaseUserManager):

    def create_user(self, username, email, password, **extra_fields):

        if not username:
            raise ValueError(_('The username must be set'))
        if not email:
            raise ValueError(_('The Email must be set'))
        
        username = username
        email = self.normalize_email(email)
        user = self.model(username = username, email = email, **extra_fields)
        user.set_password(password)
        user.save()
        return user

    def create_superuser(self, username, email, password, **extra_fields):
        """
        Create and save a SuperUser with the given email and password.
        """
        extra_fields.setdefault('is_staff', True)
        extra_fields.setdefault('is_superuser', True)
        extra_fields.setdefault('is_active', True)

        if extra_fields.get('is_staff') is not True:
            raise ValueError(_('Superuser must have is_staff=True.'))
        if extra_fields.get('is_superuser') is not True:
            raise ValueError(_('Superuser must have is_superuser=True.'))
        return self.create_user(username, email, password, **extra_fields)

serializers.py есть отдельные сериализаторы регистрации и получения для каждого класса, а пользовательский пользовательский только для тестирования, он также является основным

настройки, связанные с django rest auth

AUTH_USER_MODEL = 'users.CustomUser'

# ACCOUNT_ADAPTER = 'users.adapter.CustomAccountAdapter'


ACCOUNT_USER_MODEL_USERNAME_FIELD = 'username'
ACCOUNT_UNIQUE_USERNAME = False
ACCOUNT_EMAIL_REQUIRED = True
ACCOUNT_UNIQUE_EMAIL = True
ACCOUNT_USERNAME_REQUIRED = True
ACCOUNT_AUTHENTICATION_METHOD = 'email'
ACCOUNT_EMAIL_VERIFICATION = 'optional'
ACCOUNT_CONFIRM_EMAIL_ON_GET = True
ACCOUNT_EMAIL_CONFIRMATION_ANONYMOUS_REDIRECT_URL = '/?verification=1'
ACCOUNT_EMAIL_CONFIRMATION_AUTHENTICATED_REDIRECT_URL = '/?verification=1'

SITE_ID = 1
EMAIL_BACKEND = 'django.core.mail.backends.console.EmailBackend'

спасибо за помощь

 def save(self, request):
        try:

           user = super(TransporteurCustomRegistrationSerializer, 
       self).save(request)
           user.is_transporteur = True
    

        user.username = self.data.get('username')
        user.email = self.data.get('email')
        user.first_name = self.data.get('first_name')
        user.last_name = self.data.get('last_name')
        user.phone_number = self.data.get('phone_number')
        user.address = self.data.get('address')
        user.matricule = self.data.get('matricule')
        user.car_type = self.data.get('car_type')
        user.save()
        except IntegrityError:
             raise ValidationError("User with this email already exist")
       

       transporteur = Trasporteur(
            user=user,
            email=self.cleaned_data.get('email'), 
            first_name=self.cleaned_data.get('first_name'), 
            last_name=self.cleaned_data.get('last_name'), 
            phone_number = self.cleaned_data.get('phone_number'),
            address = self.cleaned_data.get('address'),
            matricule=self.cleaned_data.get('matricule'), 
            car_type=self.cleaned_data.get('car_type'),
            )
        transporteur.save()
        return user