Django - two approaches to extending user model wont work together?

Question

I am trying to make my django app require a unique email address when creating the account. When I added (the commented line in the models) the unique email constraint in the model I used to add fields before it just adds another email field instead of altering the original one.

So after having found another solution with extending the AbstractUser class unfortunately Im getting 'the model User is not registered' error when im trying to make migrations.

Please advice me on what would be a way to go to have both extra fields as well as unique email constraint.

Heres how i have extra fields added to the user model:

models

class Account(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    points = models.IntegerField(default=0)
    #### email = models.EmailField(("email address"), blank=True, null=True, unique=True)
    profession = models.CharField(max_length=30, blank=True, null=True,
                                              choices =[('a', 'a'), ('b', 'b')])
    def __str__(self):
        return self.user.username

admin

from django.contrib import admin
from account.models import Account
from django.contrib.auth.models import User
from django.contrib.auth.admin import UserAdmin

class AccountInline(admin.StackedInline):
    model = Account
    can_delete = False
    verbose_name_plural = 'Accounts'
    
class CustomizedUserAdmin (UserAdmin):
    inlines = (AccountInline, )

admin.site.unregister(User)
admin.site.register(User, CustomizedUserAdmin)

It worked until ive added:

models

from django.contrib.auth.models import AbstractUser

class CustomUser(AbstractUser):
    email = models.EmailField(unique=True)

settings

AUTH_USER_MODEL = 'account.CustomUser'

Answer 1

You should use one of the user models not both whether to use "User" or "CustomUser".

So, in your models:

class Account(models.Model):
user = models.OneToOneField(CustomUser, on_delete=models.CASCADE)

In your admin do the same.

Answer 2

From the moment you declare AUTH_USER_MODEL = 'account.CustomUser' you have to use it as the only one valid user model. So the error totally makes sense as you are using Django user model in admin. Adjust admin to use CustomUser model and you are probably good to go.