SSOログインが断続的に機能していません。「アカウントに問題があります。サイト管理者に連絡してください。」と表示されます。

SSOログインが断続的に機能しません。SSO設定のためにDiscourseConnectのドキュメントに従っています。ほぼ1年間正常に機能していましたが、一部のユーザーで「アカウントに問題があります。サイトの管理者に連絡してください。」と表示されます。

ただし、同じユーザーが1〜2日後にログインすると正常に機能します。
詳細ログを有効にすると、以下のログが表示されますが、原因がわかりません。

Message (308 copies reported)

Job exception: Access Denied

Backtrace

/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-core-3.130.2/lib/seahorse/client/plugins/raise_response_errors.rb:17:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-s3-1.114.0/lib/aws-sdk-s3/plugins/sse_cpk.rb:24:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-s3-1.114.0/lib/aws-sdk-s3/plugins/dualstack.rb:27:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-s3-1.114.0/lib/aws-sdk-s3/plugins/accelerate.rb:56:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-core-3.130.2/lib/aws-sdk-core/plugins/checksum_algorithm.rb:111:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-core-3.130.2/lib/aws-sdk-core/plugins/jsonvalue_converter.rb:22:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-core-3.130.2/lib/aws-sdk-core/plugins/idempotency_token.rb:19:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-core-3.130.2/lib/aws-sdk-core/plugins/param_converter.rb:26:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-core-3.130.2/lib/seahorse/client/plugins/request_callback.rb:71:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-core-3.130.2/lib/aws-sdk-core/plugins/response_paging.rb:12:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-core-3.130.2/lib/seahorse/client/plugins/response_target.rb:24:in `call'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-core-3.130.2/lib/seahorse/client/request.rb:72:in `send_request'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/aws-sdk-s3-1.114.0/lib/aws-sdk-s3/client.rb:4362:in `get_bucket_lifecycle_configuration'
/var/www/discourse/lib/s3_helper.rb:203:in `update_lifecycle'
/var/www/discourse/lib/s3_helper.rb:234:in `update_tombstone_lifecycle'
/var/www/discourse/lib/file_store/s3_store.rb:205:in `purge_tombstone'
/var/www/discourse/app/jobs/scheduled/purge_deleted_uploads.rb:9:in `execute'
/var/www/discourse/app/jobs/base.rb:292:in `block (2 levels) in perform'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/rails_multisite-5.0.0/lib/rails_multisite/connection_management.rb:82:in `with_connection'
/var/www/discourse/app/jobs/base.rb:279:in `block in perform'
/var/www/discourse/app/jobs/base.rb:275:in `each'
/var/www/discourse/app/jobs/base.rb:275:in `perform'
/var/www/discourse/app/jobs/base.rb:346:in `perform'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/mini_scheduler-0.16.0/lib/mini_scheduler/manager.rb:122:in `process_queue'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/mini_scheduler-0.16.0/lib/mini_scheduler/manager.rb:70:in `worker_loop'
/var/www/discourse/vendor/bundle/ruby/3.2.0/gems/mini_scheduler-0.16.0/lib/mini_scheduler/manager.rb:59:in `block (2 levels) in ensure_worker_threads'

原因を教えていただけますか?

何か問題の原因について、何かご存知の方はいらっしゃいますか?