Django 사용자 모델 상속이 작동하지 않습니다.

내 Django 앱에는 Retailer와 Customer의 두 가지 모델이 있습니다. 둘 다 모델 필드는 다르지만 인증을위한 공통 필드는 이메일과 비밀번호입니다. 그래서 저는 User Model Inheritance를 사용했습니다. 이것은 내 코드입니다.

상속 이유 : 토큰 인증을 구현하고 싶습니다

models.py

class User(AbstractUser):
    
    email = models.EmailField(_('email address'), unique=True)

    USERNAME_FIELD = 'email'
    EMAIL_FIELD = 'email'
    REQUIRED_FIELDS = []

    objects = UserManager()

    def __str__(self):
        return self.email

class Retailer(User, PermissionsMixin):

    name = models.CharField(max_length=255)
    phoneNUMBER = models.CharField(max_length=10)
    verificationSTATUS = models.BooleanField(default=False)
    dateJOINED = models.DateField(default=timezone.now)

    USERNAME_FIELD = 'email'
    EMAIL_FIELD = 'email'    
 
    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = ['name', 'phoneNUMBER',]
 
    objects = RetailerManager()
 
    def __str__(self):
        return self.name
 
class Customer(User, PermissionsMixin):

    name=models.CharField( max_length=255, null=False,)
    phone_Number=models.CharField( max_length=10, null=False)
    address=models.TextField(max_length=255,null=False)
    pin_Code=models.CharField( max_length=6,null=False )
    anniversary_Date=models.DateField(blank=True,null=True)
    hobbies=models.TextField(blank=True,null=True)
    profession=models.CharField(blank=True,max_length=20,null=True,)
    created_At=models.DateField(default=timezone.now)

    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = ['name', 'phoneNUMBER', 'address', 'pin_Code']    

    objects = CustomerManager()

    def __str__(self):
        return (self.name)   

managers.py

class UserManager(BaseUserManager):
    """
    Custom user model manager where email is the unique identifiers
    for authentication instead of usernames.
    """
    def create_user(self, email, password, **extra_fields):
        """
        Create and save a User with the given email and password.
        """
        if not email:
            raise ValueError(_('The Email must be set'))
        email = self.normalize_email(email)
        user = self.model(email=email, **extra_fields)
        user.set_password(password)
        user.save()
        return user

    def create_superuser(self, 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(email, password, **extra_fields)
 

class RetailerManager(BaseUserManager):
 
    def create_retailer(self, name, email, phoneNUMBER, password=None):
        if email is None:
            raise TypeError('User must have an email address.')
        retailer = Retailer(
            email=self.normalize_email(email),
            name=name,
            phoneNUMBER=phoneNUMBER
            )
        retailer.set_password(password)
        retailer.save()
        return retailer

class CustomerManager(BaseUserManager):
 
    def create_customer(self, name, email, phone_Number, address, pin_Code, password=None, **extra_fields):
        if email is None:
            raise TypeError('User must have an email address.')
        customer = Customer(
            email=self.normalize_email(email),
            name=name,
            phone_Number=phone_Number,
            address=address,
            pin_Code=pin_Code,
            )
        customer.set_password(password)
        customer.save()
        return customer

내가 이것을 실행할 때

 Retailer.objects.create(email="[email protected]", name="John Doe", password="john@123", phoneNUMBER = "90909090")

이 오류가 발생합니다.

django.db.utils.IntegrityError: UNIQUE constraint failed: retailer_user.username

또한 이것을 실행하면

Customer.objects.create(email="[email protected]", name="Jane Doe", password="jane@123")

같은 오류가 발생합니다

django.db.utils.IntegrityError: UNIQUE constraint failed: retailer_user.username

아무도 내가 뭘 잘못하고 있는지 말할 수 있습니까? 이것이 최선의 접근 방식입니까? 또한 소매 업체와 고객 모두에 대해 토큰 인증을 구현하려면 어떻게해야합니까?