diff --git a/src/TodoList.php b/src/TodoList.php
index c17252f..c777d3e 100644
--- a/src/TodoList.php
+++ b/src/TodoList.php
@@ -43,7 +43,7 @@ class TodoList
         return $this->todos;
     }
 
-    public function getTodoById(int $id): ?Todo
+    public function getTodoById(int $id): Todo
     {
         foreach ($this->todos as $todo) {
             if ($todo->getID() == $id) {