Hello! I have structure: Post → Author and Post → Shared → Author. But my nested associations for Author inside Shared doesn’t work.

I got error: ** (KeyError) key :author not found in: #Ecto.Association.NotLoaded<association :shared is not loaded>

Here is my code:

def list_posts_by_author(params) do
{stamp, “”} = Integer.parse(params[“stamp”])
author = params[“author_id”]

stamp = 
  with {:ok, stamp} <- DateTime.from_unix(stamp, :millisecond) do
    DateTime.to_naive(stamp) else err -> err
  end

(from p in Post, 

  preload: [shared: :author],
  preload: [:author],
  where: p.inserted_at < ^stamp,
  where: p.author_id == ^author) 

  |> order_by(desc: :inserted_at)
  |> Repo.all()

end

Thank you!