Authentication failure: Login page returns DoesNotEXist for users already in the database - django-models

Question

I am trying to grasp Python Django. I'm trying to make a bank system web application. I can register users. These users then are automatically logged in. However, after logout I cannot login the same user again. The page tells me the user does not exist
I have tried to play around with my backends.py in the terminal. when i run
$ user=User.objects.get(pk=1)
$ user
it returns the user with the id in the database. However it doesnt work with the login page. Kindly help, I have been stuck for a week.
models.py:
class UserManager(BaseUserManager):
def create_user(self, account_no, password=None, **extra_fields):
"""
Create and save a user with the given account_no and password.
"""
user = self.model(account_no=account_no, **extra_fields)
user.set_password(password)
user.save(using=self._db)
extra_fields.setdefault('is_staff', False)
extra_fields.setdefault('is_superuser', False)
return user
def create_superuser(self, email, password, **extra_fields):
"""
Creates and saves a superuser with the given email and password.
"""
user = self.create_user(email, password=password, **extra_fields)
user.is_admin = True
user.save(using=self._db)
extra_fields.setdefault('is_staff', True)
extra_fields.setdefault('account_no', False)
extra_fields.setdefault('is_superuser', True)
return user
class User(AbstractUser):
username = models.CharField(
('username'), max_length=30, unique=True, null=True, blank=True)
email = models.EmailField(unique=True, blank=True, null=True)
contact_no = models.IntegerField(unique=False, null=True,blank=True)
account_no = models.PositiveIntegerField(
unique=True,
validators=[
MinValueValidator(1000000000),
MaxValueValidator(9999999999)
])
balance = models.DecimalField(
default=0,
max_digits=12,
decimal_places=2
)
GENDER_CHOICE = (
("M", "Male"),
("F", "Female"),
)
gender = models.CharField(max_length=1, choices=GENDER_CHOICE)
birth_date = models.DateField(null=True, blank=True)
city = models.CharField(max_length=256, blank=True, null=True)
postal_code = models.PositiveSmallIntegerField(blank=True, null=True)
country = models.CharField(max_length=256, blank=True, null=True)
picture = models.ImageField(
null=True,
blank=True,
upload_to='account_pictures/',
)
objects = UserManager()
USERNAME_FIELD = 'account_no'
REQUIRED_FIELDS = ['first_name', 'last_name', ]
def __str__(self):
return str(self.full_name)
views.py:
def login_view(request):
if request.user.is_authenticated:
return redirect('home')
else:
form = UserLoginForm(request.POST)
if form.is_valid():
account_no = form.cleaned_data.get('account_no')
password = form.cleaned_data.get('password')
user = authenticate(account_no=account_no, password=password)
login(request, user, backend='accounts.backends.ModelBackend')
messages.success(request, 'Welcome, {}!'.format(user.full_name))
return redirect("home")
context = {"form": form,
"title": "Load Account Details",
}
return render(request, "accounts/login.html", context)
backends.py:
from django.contrib.auth import get_user_model
User = get_user_model()
class ModelBackend(object):
def authenticate(self, request, account_no=None, password=None):
try:
user = User.objects.get(account_no=account_no)
if user and user.check_password(password):
return user
except User.DoesNotExist:
return None
def get_user(self, user_id):
try:
return User.objects.get(pk=user_id)
except User.DoesNotExist:
return None
forms.py:
class UserLoginForm(forms.Form):
account_no = forms.IntegerField(label="Account Number")
password = forms.CharField(widget=forms.PasswordInput)
def clean(self, *args, **kwargs):
account_no = self.cleaned_data.get("account_no")
password = self.cleaned_data.get("password")
if account_no and password:
user = authenticate(account_no=account_no, password=password)
if not user:
raise forms.ValidationError("Account Does Not Exist.")
if not user.check_password(password):
raise forms.ValidationError("Password Does not Match.")
if not user.is_active:
raise forms.ValidationError("Account is not Active.")
return super(UserLoginForm, self).clean(*args, **kwargs)
The user that has been registered should be able to login. The program keeps denying registered users from logging in.