Manager isn't available in django

Question

My Register view is like below.

class UserRegisterView( FormView ):
    template_name = 'register.html'
    form_class = UserCreationForm
    
    redirect_authenticated_user = True
    success_url = reverse_lazy('dashboard')  # name of URL     

    def form_valid( self, form ):
        user = form.save()
        if user is not None:
            login( self.request, user )
        return super( UserRegisterView, self ).form_valid( form )
    
    def get( self, *args, **kwargs ):
        if self.request.user.is_authenticated:
            return redirect('register')
        return super( UserRegisterView, self ).get( *args, **kwargs )

My model is like below.

from django.db import models
from django.contrib.auth.models import AbstractUser

# Create your models here.

class User(AbstractUser):
    GENDER_CHOICES = (
        ('M', 'Male'),
        ('F', 'Female'),
        ('O', 'Other'),
    )

    USER_TYPE = (
        ('S', 'Super Admin'),
        ('A', 'Admin'),
        ('P', 'Patient'),
        ('D', 'Doctor'),
        ('U', 'User'),
    )

    first_name = models.CharField(max_length=255)
    last_name = models.CharField(max_length=255)
    date_of_birth = models.DateField(null=True, blank=True )
    gender = models.CharField(max_length=1, choices=GENDER_CHOICES)
    user_type = models.CharField(max_length=1, choices=USER_TYPE)
    username = models.EmailField(unique=True)
    email = models.EmailField(unique=True)
    phone = models.CharField(max_length=15, blank=True, null=True)
    address = models.TextField(blank=True, null=True)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)
    active = models.BooleanField(default=True)

    
    REQUIRED_FIELDS = []


    def __str__(self):
        return f"{self.first_name} {self.last_name}"

I am getting error Manager isn't available; 'auth.User' has been swapped for 'hospital.User'

I checked this post and applied the solution but I am getting same error again.

Here is the full traceback.

AttributeError at /register/

Manager isn't available; 'auth.User' has been swapped for 'hospital.User'

Request Method: POST Request URL: http://127.0.0.1:8000/register/ Django Version: 5.0.2 Exception Type: AttributeError Exception Value:

Manager isn't available; 'auth.User' has been swapped for 'hospital.User'

Exception Location: /home/foysal/.local/lib/python3.10/site-packages/django/db/models/manager.py, line 196, in get Raised during: hospital.views.UserRegisterView Python Executable: /usr/bin/python Python Version: 3.10.12 Python Path:

['/home/foysal/Documents/pYtHoN/hospital_management', '/usr/lib/python310.zip', '/usr/lib/python3.10', '/usr/lib/python3.10/lib-dynload', '/home/foysal/.local/lib/python3.10/site-packages', '/usr/local/lib/python3.10/dist-packages', '/usr/lib/python3/dist-packages']

Server time: Tue, 14 May 2024 06:52:53 +0000