diff --git a/.github/workflows/static.yml b/.github/workflows/static.yml
index 5d28c145..bfb9fd71 100644
--- a/.github/workflows/static.yml
+++ b/.github/workflows/static.yml
@@ -19,4 +19,4 @@ jobs:
       - name: PHP-CS-Fixer
         uses: docker://jakzal/phpqa:php8.0
         with:
-          args: php-cs-fixer fix --config=.php_cs.dist.php --dry-run
+          args: php-cs-fixer fix --config=.php_cs.dist.php --dry-run --diff
diff --git a/composer.json b/composer.json
index 0d4200f2..4be49cb7 100644
--- a/composer.json
+++ b/composer.json
@@ -22,6 +22,7 @@
         "phpspec/prophecy-phpunit": "^2.0",
         "phpunit/phpunit": "^9.5",
         "symfony/form": "^4.4|^5.3|^6.0",
+        "symfony/phpunit-bridge": "^6.2",
         "symfony/property-access": "^4.4|^5.3|^6.0",
         "symfony/serializer": "^4.4|^5.3|^6.0.1",
         "symfony/twig-bundle": "^4.4|^5.3|^6.0",
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 6bb3cb6f..3f252c42 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,6 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
 <phpunit bootstrap="./vendor/autoload.php" colors="true">
+    <php>
+        <env name="SYMFONY_DEPRECATIONS_HELPER" value="999999" />
+    </php>
     <testsuites>
         <testsuite name="MisdPhoneNumberBundle Test Suite">
             <directory>tests</directory>
@@ -11,4 +14,7 @@
             <directory>src</directory>
         </whitelist>
     </filter>
+    <listeners>
+        <listener class="\Symfony\Bridge\PhpUnit\SymfonyTestsListener" />
+    </listeners>
 </phpunit>
diff --git a/src/Serializer/Normalizer/PhoneNumberNormalizer.php b/src/Serializer/Normalizer/PhoneNumberNormalizer.php
index 4b35bda8..bb6edf09 100644
--- a/src/Serializer/Normalizer/PhoneNumberNormalizer.php
+++ b/src/Serializer/Normalizer/PhoneNumberNormalizer.php
@@ -101,6 +101,14 @@ public function denormalize($data, $class, $format = null, array $context = []):
      */
     public function supportsDenormalization($data, $type, $format = null, array $context = []): bool
     {
-        return 'libphonenumber\PhoneNumber' === $type && \is_string($data);
+        return PhoneNumber::class === $type && \is_string($data);
+    }
+
+    /**
+     * for symfony/serializer >= 6.3.
+     */
+    public function getSupportedTypes(?string $format): array
+    {
+        return [PhoneNumber::class => false];
     }
 }