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Question about limit in Ecto, Absinthe and Dataloader

Hi!
I have a Category and Product relation.
Category has_many Products,
Products belongs_to Category.

I want to get all category and get 10 items for each category for my home screen.

in schema.ex

@desc "Get all categories"
field :categories, list_of(:category) do
  resolve(&Resolvers.Category.get_categories/3)
end

object :category do
  field :name, non_null(:string)
  field :products, list_of(:product) do
    arg :limit, type: :integer, default_value: 20
    resolve dataloader(Products, :products, arg: %{scope: :category})
end

in products.ex

def datasource() do
  Dataloader.Ecto.new(MyApp.Repo, query: &query/2)
end

def query(Product, %{scope: :category, limit: limit}) do
  Product
  |> where(active: true)
  |> limit(^limit)
end

def query(queryable, _) do
  queryable
end

in resolvers.category.ex

def get_categories(_, _, _) do
  {:ok, Category.get_categories()}
end

in category.ex

def get_categories() do
  Repo.all from c in Category
end

in graphiql query I tried

{
  categories {
    name
    products(limit: 10) {
      name
    }
  }
}

But it seems not working correctly.
it returns all categories but empty product and only one category returns 10 products
what am I doing wrong?

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