diff --git a/Form/Handler/AuthorizeFormHandler.php b/Form/Handler/AuthorizeFormHandler.php
index 060359b5..f182c3f2 100644
--- a/Form/Handler/AuthorizeFormHandler.php
+++ b/Form/Handler/AuthorizeFormHandler.php
@@ -57,7 +57,7 @@ public function __construct(FormInterface $form, $requestStack = null)
      *
      * @param ContainerInterface|null $container A ContainerInterface instance or null
      */
-    public function setContainer(ContainerInterface $container = null)
+    public function setContainer(?ContainerInterface $container = null)
     {
         $this->container = $container;
     }
diff --git a/Security/EntryPoint/OAuthEntryPoint.php b/Security/EntryPoint/OAuthEntryPoint.php
index cdf87af2..bef93054 100644
--- a/Security/EntryPoint/OAuthEntryPoint.php
+++ b/Security/EntryPoint/OAuthEntryPoint.php
@@ -29,7 +29,7 @@ public function __construct(OAuth2 $serverService)
         $this->serverService = $serverService;
     }
 
-    public function start(Request $request, AuthenticationException $authException = null): Response
+    public function start(Request $request, ?AuthenticationException $authException = null): Response
     {
         $exception = new OAuth2AuthenticateException(
             Response::HTTP_UNAUTHORIZED,
diff --git a/Storage/OAuthStorage.php b/Storage/OAuthStorage.php
index bb0bc86b..1860e9aa 100644
--- a/Storage/OAuthStorage.php
+++ b/Storage/OAuthStorage.php
@@ -59,8 +59,8 @@ public function __construct(
         AccessTokenManagerInterface $accessTokenManager,
         RefreshTokenManagerInterface $refreshTokenManager,
         AuthCodeManagerInterface $authCodeManager,
-        UserProviderInterface $userProvider = null,
-        PasswordHasherFactoryInterface $passwordHasherFactory = null
+        ?UserProviderInterface $userProvider = null,
+        ?PasswordHasherFactoryInterface $passwordHasherFactory = null
     ) {
         $this->clientManager = $clientManager;
         $this->accessTokenManager = $accessTokenManager;