I get the error "Cannot resolve keyword 'category' into field. Choices are: id" in MPTT

Question

I want to create a subcategory with MPTT but I get the error "Cannot resolve keyword 'category' into field. Choices are: id". I can't find the reason. I would be happy if you half. I'm trying to edit dressing on the admin page. I'm trying to do this from a source I found on the internet. source:https://django-mptt.readthedocs.io/en/latest/models.html

models.py

from django.db import models
from mptt.models import MPTTModel, TreeForeignKey

# Create your models here.

class Category(MPTTModel):
  name = models.CharField(max_length=100)
  slug = models.SlugField(max_length=100, unique=True)
  keywords = models.CharField(max_length=100)
  parent = TreeForeignKey('self', on_delete=models.CASCADE, blank=True, null=True, 
  related_name='children')

  class MPTTMeta:
    order_insertion_by = ['name']
  def __str__(self):
    return self.name

class Product(models.Model):
  pass

admin.py

from django.contrib import admin
from mptt.admin import DraggableMPTTAdmin
from .models import Category, Product
# Register your models here.

class CategoryAdmin(DraggableMPTTAdmin):
   prepopulated_fields = {'slug': ('name',)}
   mptt_indent_field = "name"
   list_display = ('tree_actions', 'indented_title',
                'related_products_count', 'related_products_cumulative_count')
   list_display_links = ('indented_title',)

   def get_queryset(self, request):
      qs = super().get_queryset(request)

    qs = Category.objects.add_related_count(
            qs,
            Product,
            'category',
            'products_cumulative_count',
            cumulative=True)

    qs = Category.objects.add_related_count(qs,
             Product,
             'categories',
             'products_count',
             cumulative=False)
    return qs

def related_products_count(self, instance):
    return instance.products_count
related_products_count.short_description = 'Kataqoriada olan məhsulların sayı'

def related_products_cumulative_count(self, instance):
    return instance.products_cumulative_count
related_products_cumulative_count.short_description = 'Alt kataqoriada olan məhsulların sayı'

admin.site.register(Product)
admin.site.register(Category, CategoryAdmin)

Error: