Rails でlocalhostが表示されません

前提・実現したいこと

どこかいじってしまったようでRailsでrails sを実行してもlocalhostが表示されなくて困っています。
以下のような長いエラーコードが出てきます。

発生している問題・エラーメッセージ

Puma caught this error: undefined method `delete' for nil:NilClass (NoMethodError)
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activerecord-6.0.3.1/lib/active_record/railtie.rb:179:in `block (2 levels) in <class:Railtie>'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/lazy_load_hooks.rb:71:in `class_eval'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/lazy_load_hooks.rb:71:in `block in execute_hook'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/lazy_load_hooks.rb:61:in `with_execution_control'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/lazy_load_hooks.rb:66:in `execute_hook'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/lazy_load_hooks.rb:52:in `block in run_load_hooks'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/lazy_load_hooks.rb:51:in `each'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/lazy_load_hooks.rb:51:in `run_load_hooks'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activerecord-6.0.3.1/lib/active_record/base.rb:327:in `<module:ActiveRecord>'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activerecord-6.0.3.1/lib/active_record/base.rb:27:in `<main>'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/bootsnap-1.4.6/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:23:in `require'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/bootsnap-1.4.6/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:23:in `block in require_with_bootsnap_lfi'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/bootsnap-1.4.6/lib/bootsnap/load_path_cache/loaded_features_index.rb:92:in `register'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/bootsnap-1.4.6/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in `require_with_bootsnap_lfi'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/bootsnap-1.4.6/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:31:in `require'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/zeitwerk-2.3.0/lib/zeitwerk/kernel.rb:23:in `require'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activerecord-6.0.3.1/lib/active_record/query_cache.rb:31:in `run'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/execution_wrapper.rb:28:in `before'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:428:in `block in make_lambda'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:200:in `block (2 levels) in halting'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:605:in `block (2 levels) in default_terminator'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:604:in `catch'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:604:in `block in default_terminator'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:201:in `block in halting'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:513:in `block in invoke_before'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:513:in `each'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:513:in `invoke_before'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/callbacks.rb:134:in `run_callbacks'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/execution_wrapper.rb:111:in `run!'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/execution_wrapper.rb:73:in `block in run!'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/execution_wrapper.rb:70:in `tap'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.1/lib/active_support/execution_wrapper.rb:70:in `run!'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/actionpack-6.0.3.1/lib/action_dispatch/middleware/executor.rb:12:in `call'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/actionpack-6.0.3.1/lib/action_dispatch/middleware/static.rb:126:in `call'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/rack-2.2.2/lib/rack/sendfile.rb:110:in `call'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/actionpack-6.0.3.1/lib/action_dispatch/middleware/host_authorization.rb:82:in `call'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/webpacker-4.2.2/lib/webpacker/dev_server_proxy.rb:23:in `perform_request'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/rack-proxy-0.6.5/lib/rack/proxy.rb:57:in `call'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/railties-6.0.3.1/lib/rails/engine.rb:527:in `call'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/puma-4.3.5/lib/puma/configuration.rb:228:in `call'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/puma-4.3.5/lib/puma/server.rb:713:in `handle_request'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/puma-4.3.5/lib/puma/server.rb:472:in `process_client'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/puma-4.3.5/lib/puma/server.rb:328:in `block in run'
/Users/kaito/kaito_app/vendor/bundle/ruby/2.7.0/gems/puma-4.3.5/lib/puma/thread_pool.rb:134:in `block in spawn_thread'