seedsでカテゴリ用のデータを追加できない

前提

ruby on railsで家計簿アプリを作成しています。
親、子、孫の3層を持つカテゴリを実装するためにancestryというgemを使おうとしたところCategoryテーブルに追加することができませんでした。

実現したいこと

seeds.rbを使って最初のカテゴリの要素を追加したい。

発生している問題・エラーメッセージ

** Invoke db:seed (first_time)
** Invoke db:load_config (first_time)
** Invoke environment (first_time)
** Execute environment
** Execute db:load_config
** Execute db:seed
** Invoke db:abort_if_pending_migrations (first_time)
** Invoke db:load_config 
** Execute db:abort_if_pending_migrations
rake aborted!
ArgumentError: The scope body needs to be callable.
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activerecord-6.1.5/lib/active_record/scoping/named.rb:156:in `scope'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/ancestry-1.3.0/lib/ancestry/has_ancestry.rb:44:in `has_ancestry'
/home/user/environment/kakeibo/app/models/category.rb:3:in `<class:Category>'
/home/user/environment/kakeibo/app/models/category.rb:1:in `<main>'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/bootsnap-1.11.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in `require'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/bootsnap-1.11.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:30:in `require'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/zeitwerk-2.5.4/lib/zeitwerk/kernel.rb:27:in `require'
/home/user/environment/kakeibo/db/seeds.rb:11:in `<main>'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/bootsnap-1.11.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:39:in `load'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/bootsnap-1.11.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:39:in `load'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/railties-6.1.5/lib/rails/engine.rb:566:in `block in load_seed'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/callbacks.rb:117:in `block in run_callbacks'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/execution_wrapper.rb:91:in `wrap'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/railties-6.1.5/lib/rails/engine.rb:640:in `block (2 levels) in <class:Engine>'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/callbacks.rb:126:in `instance_exec'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/callbacks.rb:126:in `block in run_callbacks'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/callbacks.rb:137:in `run_callbacks'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/railties-6.1.5/lib/rails/engine.rb:566:in `load_seed'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activerecord-6.1.5/lib/active_record/tasks/database_tasks.rb:450:in `load_seed'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activerecord-6.1.5/lib/active_record/railties/databases.rake:392:in `block (2 levels) in <main>'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/task.rb:281:in `block in execute'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/task.rb:281:in `each'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/task.rb:281:in `execute'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/task.rb:219:in `block in invoke_with_call_chain'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/task.rb:199:in `synchronize'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/task.rb:199:in `invoke_with_call_chain'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/task.rb:188:in `invoke'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/application.rb:160:in `invoke_task'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/application.rb:116:in `block (2 levels) in top_level'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/application.rb:116:in `each'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/application.rb:116:in `block in top_level'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/application.rb:125:in `run_with_threads'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/application.rb:110:in `top_level'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/application.rb:83:in `block in run'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/application.rb:186:in `standard_exception_handling'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/rake-13.0.6/lib/rake/application.rb:80:in `run'
/home/user/environment/kakeibo/bin/rake:5:in `<main>'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/bootsnap-1.11.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:39:in `load'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/bootsnap-1.11.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:39:in `load'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/fork_tracker.rb:10:in `block in fork'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/fork_tracker.rb:10:in `block in fork'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/fork_tracker.rb:8:in `fork'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/fork_tracker.rb:8:in `fork'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/fork_tracker.rb:27:in `fork'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/fork_tracker.rb:8:in `fork'
/home/user/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/activesupport-6.1.5/lib/active_support/fork_tracker.rb:27:in `fork'
<internal:/home/user/.rbenv/versions/3.0.2/lib/ruby/site_ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require'
<internal:/home/user/.rbenv/versions/3.0.2/lib/ruby/site_ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require'
-e:1:in `<main>'
Tasks: TOP => db:seed

該当のソースコード

category.rb

ruby
1class Category < ApplicationRecord
2  has_many :posts
3  has_ancestry
4
5  validates :name, presence: true
6end

seeds.rb
1income = Category.create(name: '収入')
2i1 = income.children.create(name: '給与')
3i1.children.create([{ name: '給料' }, { name: 'アルバイト' }, { name: '小遣い' }, { name: 'その他' }])
4
5# ...以下同じようなコードが続く