diff --git a/src/Api/ApigeeX/Controller/AppByOwnerController.php b/src/Api/ApigeeX/Controller/AppByOwnerController.php
index 83a0b167..55a2f7fc 100644
--- a/src/Api/ApigeeX/Controller/AppByOwnerController.php
+++ b/src/Api/ApigeeX/Controller/AppByOwnerController.php
@@ -45,7 +45,7 @@ abstract class AppByOwnerController extends PaginatedEntityController implements
      * @param ClientInterface $client
      * @param EntitySerializerInterface|null $entitySerializer
      */
-    public function __construct(string $organization, ClientInterface $client, ?EntitySerializerInterface $entitySerializer = null)
+    public function __construct(string $organization, ClientInterface $client, EntitySerializerInterface $entitySerializer = null)
     {
         $entitySerializer = $entitySerializer ?? new AppEntitySerializer();
         parent::__construct($organization, $client, $entitySerializer);
diff --git a/src/Api/ApigeeX/Controller/AppGroupAppController.php b/src/Api/ApigeeX/Controller/AppGroupAppController.php
index 4c2b37e8..f7c18fc9 100644
--- a/src/Api/ApigeeX/Controller/AppGroupAppController.php
+++ b/src/Api/ApigeeX/Controller/AppGroupAppController.php
@@ -52,8 +52,8 @@ public function __construct(
         string $organization,
         string $appGroup,
         ClientInterface $client,
-        ?EntitySerializerInterface $entitySerializer = null,
-        ?OrganizationControllerInterface $organizationController = null
+        EntitySerializerInterface $entitySerializer = null,
+        OrganizationControllerInterface $organizationController = null
     ) {
         $this->appGroup = $appGroup;
         $entitySerializer = $entitySerializer ?? new AppGroupEntitySerializer();