diff --git a/changelog.md b/changelog.md
index 847bc00..42a5e40 100644
--- a/changelog.md
+++ b/changelog.md
@@ -106,4 +106,7 @@
 
 ### Next
 #### Improve
-- Upgrade to Symfony 5.3
\ No newline at end of file
+- Upgrade to Symfony 5.3
+
+#### Fix
+- Add 404 error when invalid ID
\ No newline at end of file
diff --git a/src/Controller/ActivityController.php b/src/Controller/ActivityController.php
index 283edc3..ffe29ba 100644
--- a/src/Controller/ActivityController.php
+++ b/src/Controller/ActivityController.php
@@ -16,6 +16,7 @@
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Routing\Generator\UrlGenerator;
+use Symfony\Component\Routing\Exception\ResourceNotFoundException;
 
 /**
  * Controller for activity related pages
@@ -132,6 +133,9 @@
 
         // Get activity
         $activity = $activityRepository->find($id);
+        if(is_null($activity)) {
+            throw new ResourceNotFoundException();
+        }
 
         // Get actors
         $actors = $actorRepository->findAll();
diff --git a/src/Controller/ActorController.php b/src/Controller/ActorController.php
index 3dc4b59..c9a0f54 100644
--- a/src/Controller/ActorController.php
+++ b/src/Controller/ActorController.php
@@ -14,6 +14,7 @@
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Routing\Generator\UrlGenerator;
+use Symfony\Component\Routing\Exception\ResourceNotFoundException;
 
 class ActorController extends AbstractExtendedController
 {
@@ -113,6 +114,9 @@
 
         // Get actor
         $actor = $actorRepository->find($id);
+        if(is_null($actor)) {
+            throw new ResourceNotFoundException();
+        }
 
         // Actor edit form
         /** @var ActorEditForm $actorEditForm */
diff --git a/src/Controller/TaskController.php b/src/Controller/TaskController.php
index 5b8b327..761628c 100644
--- a/src/Controller/TaskController.php
+++ b/src/Controller/TaskController.php
@@ -12,6 +12,7 @@
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Routing\Generator\UrlGenerator;
 use App\Form\Task\TaskFilterForm;
+use Symfony\Component\Routing\Exception\ResourceNotFoundException;
 
 class TaskController extends AbstractExtendedController
 {
@@ -122,6 +123,9 @@
 
         // Get task
         $task = $taskRepository->find($id);
+        if(is_null($task)) {
+            throw new ResourceNotFoundException();
+        }
 
         // Get actors
         $actors = $actorRepository->findAll();