Sidekiq/Redis/Rails - Sending was working on the branch, but now will not deliver on development

Ruby version: 2.6.5Rails version: 6.1.3.1Sidekiq / Pro / Enterprise version(s): 6.2

Initializer: No initializer

Sidekiq.yml:

:verbose: true:concurrency: 25:queues: - [mailers, 7] - [default, 5]

Error Messages: NONE

Full Sidekiq Backtrace:

****** (development) $ bundle exec sidekiq               m,               `$b          .ss,  $$:         .,d$          `$$P,d$P'    .,md$P"'           ,$$$$$b/md$$$P^'         .d$$$$$$/$$$P'         $$^' `"/$$$'       ____  _     _      _    _         $:     ,$$:       / ___|(_) __| | ___| | _(_) __ _         `b     :$$        \___ \| |/ _` |/ _ \ |/ / |/ _` |                $$:         ___) | | (_| |  __/   <| | (_| |                $$         |____/|_|\__,_|\___|_|\_\_|\__, |              .d$$                                       |_|2021-06-13T15:22:14.594Z pid=756 tid=oxyx50z9s INFO: Booted Rails 6.1.3.1 application in development environment2021-06-13T15:22:14.594Z pid=756 tid=oxyx50z9s INFO: Running in ruby 2.6.5p114 (2019-10-01 revision 67812) [x86_64-linux]2021-06-13T15:22:14.594Z pid=756 tid=oxyx50z9s INFO: See LICENSE and the LGPL-3.0 for licensing details.2021-06-13T15:22:14.595Z pid=756 tid=oxyx50z9s INFO: Upgrade to Sidekiq Pro for more features and support: https://sidekiq.org2021-06-13T15:22:14.595Z pid=756 tid=oxyx50z9s INFO: Booting Sidekiq 6.2.1 with redis options {}2021-06-13T15:22:14.597Z pid=756 tid=oxyx50z9s DEBUG: Client Middleware:2021-06-13T15:22:14.597Z pid=756 tid=oxyx50z9s DEBUG: Server Middleware: Raven::Sidekiq::CleanupMiddleware2021-06-13T15:22:14.598Z pid=756 tid=oxyx50z9s INFO: Starting processing, hit Ctrl-C to stop2021-06-13T15:22:14.598Z pid=756 tid=oxyx50z9s DEBUG: {:queues=>["mailers", "mailers", "mailers", "mailers", "mailers", "mailers", "mailers", "default", "default", "default", "default", "default"], :labels=>[], :concurrency=>25, :require=>".", :strict=>false, :environment=>nil, :timeout=>25, :poll_interval_average=>nil, :average_scheduled_poll_interval=>5, :error_handlers=>[#<Sidekiq::ExceptionHandler::Logger:0x00007ffff8446a88>, #<Raven::Sidekiq::ErrorHandler:0x00007ffffa9bddc0>], :death_handlers=>[], :lifecycle_events=>{:startup=>[], :quiet=>[], :shutdown=>[], :heartbeat=>[]}, :dead_max_jobs=>10000, :dead_timeout_in_seconds=>15552000, :reloader=>#<Sidekiq::Rails::Reloader @app=Bdcommunity::Application>, :verbose=>true, :config_file=>"./config/sidekiq.yml", :tag=>"bdcommunity", :identity=>"DESKTOP***", :fetch=>#<Sidekiq::BasicFetch:0x00007ffffd789bc8 @options={...}, @strictly_ordered_queues=false, @queues=["queue:mailers", "queue:mailers", "queue:mailers", "queue:mailers", "queue:mailers", "queue:mailers", "queue:mailers", "queue:default", "queue:default", "queue:default", "queue:default", "queue:default"]>}2021-06-13T15:23:41.567Z pid=756 tid=oxyy3dekc class=ActionMailer::MailDeliveryJob jid=1430f4cf1b9ea1c8f7578578 INFO: start2021-06-13T15:23:41.584Z pid=756 tid=oxyy3dfsg class=ActionMailer::MailDeliveryJob jid=24dc64f44ab2088912a506e2 INFO: start2021-06-13T15:23:41.584Z pid=756 tid=oxyy0umak class=ActionMailer::MailDeliveryJob jid=dce3868b2802b2a44c964f80 INFO: start2021-06-13T15:23:41.584Z pid=756 tid=oxyy3dgjc class=ActionMailer::MailDeliveryJob jid=c85bd721343289b44218bd5d INFO: start2021-06-13T15:23:41.585Z pid=756 tid=oxyy3df2o class=ActionMailer::MailDeliveryJob jid=81d4a665cc70e7056bfee2bc INFO: start

Full Redis Backtrace:

630:M 13 Jun 2021 11:21:44.283 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.630:M 13 Jun 2021 11:21:44.283 # Server initialized630:M 13 Jun 2021 11:21:44.283 # WARNING overcommit_memory is set to 0! Background save may fail under low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.630:M 13 Jun 2021 11:21:44.283 * Loading RDB produced by version 6.2.1630:M 13 Jun 2021 11:21:44.283 * RDB age 152 seconds630:M 13 Jun 2021 11:21:44.283 * RDB memory usage when created 1.42 Mb630:M 13 Jun 2021 11:21:44.284 * DB loaded from disk: 0.000 seconds630:M 13 Jun 2021 11:21:44.284 * Ready to accept connections630:M 13 Jun 2021 11:26:45.030 * 100 changes in 300 seconds. Saving...630:M 13 Jun 2021 11:26:45.037 * Background saving started by pid 10041004:C 13 Jun 2021 11:26:45.050 * DB saved on disk630:M 13 Jun 2021 11:26:45.138 * Background saving terminated with success630:M 13 Jun 2021 11:31:46.019 * 100 changes in 300 seconds. Saving...630:M 13 Jun 2021 11:31:46.026 * Background saving started by pid 12161216:C 13 Jun 2021 11:31:46.047 * DB saved on disk630:M 13 Jun 2021 11:31:46.127 * Background saving terminated with success

Full Relevant Rails Server Backtrace:

[ActiveJob] Enqueued ActionMailer::MailDeliveryJob (Job ID: 7d4823ed-e0f8-40ec-9a25-ddac8e373de5) to Sidekiq(mailers) with arguments: "NotificationMailer", "private_message_received", "deliver_now", {:args=>[#<GlobalID:0x00007fffd89c8008 @uri=#<URI::GID gid://***>>, #<GlobalID:0x00007fffd89ff918 @uri=#<URI::GID gid://***>>, "Test Number 3"]}[ActiveJob] Enqueued ActionMailer::MailDeliveryJob (Job ID: ac28e08d-3318-41e5-83c8-83010be6a1d3) to Sidekiq(mailers) with arguments: "NotificationMailer", "private_message_received", "deliver_now", {:args=>[#<GlobalID:0x00007fffd8bbbb80 @uri=#<URI::GID gid://***>>, #<GlobalID:0x00007fffd8c006b8 @uri=#<URI::GID gid://***>>, "Test Number 3"]}[ActiveJob] Enqueued ActionMailer::MailDeliveryJob (Job ID: 87e09cd3-631e-46c3-9f2e-0e7f622d2d7a) to Sidekiq(mailers) with arguments: "NotificationMailer", "private_message_received", "deliver_now", {:args=>[#<GlobalID:0x00007fffd8ef99f0 @uri=#<URI::GID gid://***>>, #<GlobalID:0x00007fffd8f35770 @uri=#<URI::GID gid://***>>, "Test Number 3"]}[ActiveJob] Enqueued ActionMailer::MailDeliveryJob (Job ID: 3eebfc8c-faba-40d0-9edf-64e34cd1161b) to Sidekiq(mailers) with arguments: "NotificationMailer", "private_message_received", "deliver_now", {:args=>[#<GlobalID:0x00007fffd91572d8 @uri=#<URI::GID gid://***>>, #<GlobalID:0x00007fffd91796f8 @uri=#<URI::GID gid://***>>, "Test Number 3"]}[ActiveJob] Enqueued ActionMailer::MailDeliveryJob (Job ID: 26cca661-437f-4d3e-a341-02fbe53ebb6a) to Sidekiq(mailers) with arguments: "NotificationMailer", "private_message_received", "deliver_now", {:args=>[#<GlobalID:0x00007fffd934e2d0 @uri=#<URI::GID gid://***/***/**>>, #<GlobalID:0x00007fffd9352628 @uri=#<URI::GID gid://****>>, "Test Number 3"]}Completed 302 Found in 439ms (ActiveRecord: 25.8ms | Allocations: 80420)

Does anyone know why the emails are now not delivering?