(I tried solutions provided in similar questions, but they didn’t work).

I am learning Django, and building the following project:

My project is es. I have 3 apps called event, items_dashboard and item. Each event has one items_dashboard, and zero or more items.

When the user is in /event/<event_id>/items_dashboard/index.html, there is a link to add a new item to event <event_id>. This opens a form /item/new/<event_id>. When I fill and submit this form, I get the following error:

Page not found (404)
Request Method: POST
Request URL:    http://127.0.0.1:8000/item/new/
Using the URLconf defined in event_site.urls, Django tried these URL patterns, in this order:

[name='index']
event/
item/ new/<int:event_id> [name='new']
item/ <int:pk>/ [name='detail']
item/ <int:pk>/delete [name='delete_item']
The current path, item/new/, didn’t match any of these.

How do I correctly define the url for this scenario?

My relevant urls.py files are as follows:
es/urls.py:

urlpatterns = [
    path('', include('core.urls')),
    path('admin/', admin.site.urls),
    path('event/', include('event.urls', namespace="event")),
    path('item/', include('item.urls', namespace="item")),
    # path('', index, name='index')
] + static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

item/urls.py:

app_name = 'item'

urlpatterns = [
    # path('new/', views.new, name='new'),
    path('new/<int:event_id>', views.new, name='new'),
    path('<int:pk>/', views.detail, name='detail'),
]

event/urls.py:

app_name = 'event'

urlpatterns = [
    path('new/', views.new, name='new'),
    path('<int:pk>/', views.detail, name='detail'),
    path('<int:event_id>/items_dashboard/', include('items_dashboard.urls', namespace='items_dashboard')),
    path('<int:event_id>/item/', include('item.urls', namespace='item'))
]

My item/views.py has this function (from the activity, I can see that when I submit the form, the new() function is called, and the correct event_id is provided):

@login_required()
def new(request, event_id):
    event = get_object_or_404(Event, pk=event_id)
    if request.method == "POST":
        form = NewItemForm(request.POST, request.FILES)
        if form.is_valid():
            item = form.save(commit=False)
            item.event = event
            item.creator = request.user
            item.save()
            return redirect('item:detail', pk=item.id)
    else:
        form = NewItemForm()
    
    return render(request, 'item/form.html', {
        'form': form,
        'title': 'Add new item'
    })

And finally, item/templates/item/form.html:

{% extends 'core/base.html' %}

{% block title %}{{ title }}{% endblock %}

{% block content %}
<h1 class="mb-6 text-3xl">{{ title }}</h1>
<form method="post" action="." enctype="multipart/form-data">
    {% csrf_token %}

    <div class="space-y-4">
        {{ form.as_p }}
    </div>

    {% if form.errors or form.non_field_errors %}
        <div class="mb-3 p-6 bg-red-100 rounded-xl">
            {% for field in form %}
                {{ field.errors }}
            {% endfor %}

            {{ form.non_field_errors }}
        </div>
    {% endif %}

    <button class="mt-6 py-4 px-8 text-lg bg-teal-500 hover:bg-teal-700 rounded-xl text-white">Create Item</button>
</form>
{% endblock %}