diff --git a/app/helpers/action_cable_helper.rb b/app/helpers/action_cable_helper.rb
index 13027292..60fb84db 100644
--- a/app/helpers/action_cable_helper.rb
+++ b/app/helpers/action_cable_helper.rb
@@ -13,6 +13,8 @@ module ActionCableHelper
             locals: {request_for_comment: self})
         )
       end
+    rescue StandardError => e
+      Sentry.capture_exception(e)
     ensure
       ActiveRecord::Base.connection_pool.release_connection
     end
@@ -33,6 +35,8 @@ module ActionCableHelper
           working_time_data: exercise.get_working_times_for_study_group(study_group_id, user)
         )
       end
+    rescue StandardError => e
+      Sentry.capture_exception(e)
     ensure
       ActiveRecord::Base.connection_pool.release_connection
     end
diff --git a/app/models/submission.rb b/app/models/submission.rb
index 41b593d6..ae80c10d 100644
--- a/app/models/submission.rb
+++ b/app/models/submission.rb
@@ -312,6 +312,8 @@ class Submission < ApplicationRecord
           rfc.full_score_reached = true
           rfc.save
         end
+      rescue StandardError => e
+        Sentry.capture_exception(e)
       ensure
         ActiveRecord::Base.connection_pool.release_connection
       end
diff --git a/lib/prometheus/controller.rb b/lib/prometheus/controller.rb
index 84fc5192..ba6b0b53 100644
--- a/lib/prometheus/controller.rb
+++ b/lib/prometheus/controller.rb
@@ -19,6 +19,8 @@ module Prometheus
             initialize_rfc_metrics
           rescue StandardError => e
             Sentry.capture_exception(e)
+          ensure
+            ActiveRecord::Base.connection_pool.release_connection
           end
         end
       end
diff --git a/lib/runner/event_loop.rb b/lib/runner/event_loop.rb
index 037f08d0..28ccbae0 100644
--- a/lib/runner/event_loop.rb
+++ b/lib/runner/event_loop.rb
@@ -32,6 +32,8 @@ class Runner::EventLoop
       queue = Queue.new
       Thread.new do
         EventMachine.run { queue.push nil }
+      rescue StandardError => e
+        Sentry.capture_exception(e)
       ensure
         ActiveRecord::Base.connection_pool.release_connection
       end