Python Django: Customize User

Question

I only use the Rest_Api from Django 4.1 Python. Thats my project Setting:

mealSheetAI
  setting.py
   mealSheetApi
     admin.py
     models.py

models.py

from django.db import models
from django.contrib.auth.models import AbstractBaseUser, PermissionsMixin

class User(AbstractBaseUser, PermissionsMixin):
    email =  models.EmailField(
        verbose_name='email address',
        max_length=255,
        unique=True,
    )
    first_name = models.CharField(max_length=30)
    last_name = models.CharField(max_length=30)

    USERNAME_FIELD = 'email'

admin.py

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

admin.site.register(User, UserAdmin)

settings.py

AUTH_USER_MODEL = 'mealSheetApi.User'

My Problem is I can't set the User. I got an error like this:

Manager isn't available; User has been swapped for 'pet.Person'