Como corrigir "SignUpView está sem um QuerySet"

No meu aplicativo web Django, estou tentando criar um aplicativo de jornal. Na minha página inicial, quando clico no SIGN UPbotão, recebo o erro "Configurado incorretamente em /accounts/signup/". Não descobri onde está o problema. forms.py:

from django.contrib.auth.forms import UserCreationForm, UserChangeForm
from .models import CustomUser

class CustomUserCreationForm(UserCreationForm): #Creation of CustomUser

    class Meta:
        model = CustomUser
        fields = UserCreationForm.Meta.fields + ("age",) 

class CustomUserChangeForm(UserChangeForm): #Modifying existing users

    class Meta:
        model = CustomUser
        fields = UserChangeForm.Meta.fields 

emodels.py:

from django.contrib.auth.models import AbstractUser #username, pw1, pw2
from django.db import models

class CustomUser(AbstractUser):
    age = models.PositiveIntegerField(null=True, blank=True)

urls.py:

from django.urls import path
from .views import SignUpView

#Accounts/urls.py : Handles only registrations URLs!!
urlpatterns = [
    path('signup/', SignUpView.as_view(), name='signup'),
]

eviews.py:

from django.urls import reverse_lazy
from django.views.generic import CreateView
from .forms import CustomUserCreationForm

class SignUpView(CreateView):
    from_class = CustomUserCreationForm
    success_url = reverse_lazy('login')
    template_name = 'registration/signup.html'

signup.html:

{% extends 'base.html' %}

{% block title %}Sign Up{% endblock title %}

{% block content %}
<h2>Sign Up</h2>
<form method="post">
{% csrf_token %}
{{ form.as_p }}
<button type="submit">Sign Up</button>
</form>
{% endblock content %}

Tentei alterar os campos forms.pycom:

fields = (
            "username",
            "email",
            "age",)

mas nada a mencionar