成功注册用户后，登录页面返回“帐户不存在”

Question

我是Django网站开发的新手。我正在创建一个简单的银行Web应用程序。注册可以很好地进行，因为可以自动创建和登录用户。但是，当我注销用户并尝试再次登录时，页面告诉我该帐户不存在。

我认为错误出在我的views.py文件中。我试图找到错误，但正如我所说的，我是新手。请有人帮助我。

views.py：

def login_view(request):
    if request.user.is_authenticated:
        return redirect("home")
    else:
        form = UserLoginForm(request.POST or None)

        if form.is_valid():
            account_no = form.cleaned_data.get("account_no")
            password = form.cleaned_data.get("password")
            # authenticate with Account No & Password
            user = authenticate(account_no=account_no, password=password)
            if user is not None:
                login(request, user, backend='accounts.backends.AccountNoBackend')
                messages.success(request, 'Welcome, {}!' .format(user.full_name))
            return redirect("home")

        context = {"form": form,
                   "title": "Load Account Details",
                   }

        return render(request, "accounts/form.html", context)

backends.py：

from django.contrib.auth import get_user_model


User = get_user_model()


class AccountNoBackend():

    def authenticate(self, request, account_no=None, password=None):
        try:
            user = User.objects.get(account__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

models.py：

class User(AbstractUser):
    username = models.CharField(
        _('username'), max_length=30, unique=True, null=True, blank=True,
        help_text=_(
            'Required. 30 characters or fewer. Letters, digits and '
            '@/./+/-/_ only.'
        ),
        validators=[
            RegexValidator(
                r'^[\w.@+-]+$',
                _('Enter a valid username. '
                    'This value may contain only letters, numbers '
                    'and @/./+/-/_ characters.'), 'invalid'),
        ],
        error_messages={`enter code here`
            'unique': _("A user with that username already exists."),
        })

    email = models.EmailField(unique=True, null=False, blank=False)
    contact_no = models.IntegerField(blank=True, null=True)

    objects = UserManager()

    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = []

    def __str__(self):
        return self.email

    @property
    def account_no(self):
        if hasattr(self, 'account'):
            return self.account.account_no
        return None

    @property
    def full_name(self):
        return '{} {}'.format(self.first_name, self.last_name)

    @property
    def balance(self):
        if hasattr(self, 'account'):
            return self.account.balance
        return None

    @property
    def full_address(self):
        if hasattr(self, 'address'):
            return '{}, {}-{}, {}'.format(
                self.address.street_address,
                self.address.city,
                self.address.postal_code,
                self.address.country,
            )
        return None


class AccountDetails(models.Model):
    GENDER_CHOICE = (
        ("M", "Male"),
        ("F", "Female"),
    )
    user = models.OneToOneField(
        User,
        related_name='account',
        on_delete=models.CASCADE,
    )
    account_no = models.AutoField(
        unique=True,
        primary_key=True,
        null=False,
        validators=[
            MinValueValidator(10000000),
            MaxValueValidator(99999999)
        ]
    )
    gender = models.CharField(max_length=1, choices=GENDER_CHOICE)
    birth_date = models.DateField(null=True, blank=True)
    balance = models.DecimalField(
        default=0,
        max_digits=12,
        decimal_places=2
    )
    picture = models.ImageField(
        null=True,
        blank=True,
        upload_to='account_pictures/',
    )

    def __str__(self):
        return str(self.account_no)

我希望将重定向到成功页面，但找不到所需的帐号