saving works now

backend/urls.py

@@ -0,0 +1,8 @@
+from django.contrib import admin
+from django.urls import include, path
+
+urlpatterns = [
+    path('', include('backend.core.urls', namespace='core')),
+    path('accounts/', include('backend.accounts.urls')),  # without namespace
+    path('admin/', admin.site.urls),
+]