diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/RemoteEvent/MailerSendPayloadConverter.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/RemoteEvent/MailerSendPayloadConverter.php
index 1fdebf91beb0..84ffc63405f3 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/RemoteEvent/MailerSendPayloadConverter.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/RemoteEvent/MailerSendPayloadConverter.php
@@ -43,7 +43,7 @@ public function convert(array $payload): AbstractMailerEvent
             $event = new MailerEngagementEvent($name, $this->getMessageId($payload), $payload);
         }
 
-        if (!$date = \DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', $payload['created_at'])) {
+        if (!$date = \DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', $payload['created_at'])) {
             throw new ParseException(sprintf('Invalid date "%s".', $payload['created_at']));
         }
 
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/clicked.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/clicked.php
index 5ca285288014..4ec585b9d3a5 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/clicked.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/clicked.php
@@ -9,6 +9,6 @@
     'ip' => '127.0.0.1',
     'url' => 'https://www.mailersend.com'
 ]);
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/clicked_unique.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/clicked_unique.php
index 5ca285288014..4ec585b9d3a5 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/clicked_unique.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/clicked_unique.php
@@ -9,6 +9,6 @@
     'ip' => '127.0.0.1',
     'url' => 'https://www.mailersend.com'
 ]);
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/delivered.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/delivered.php
index 62558144c06a..66bc3c32b2b4 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/delivered.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/delivered.php
@@ -7,6 +7,6 @@
 $wh->setTags(["test-tag"]);
 $wh->setMetadata([]);
 $wh->setReason('');
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/hard_bounced.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/hard_bounced.php
index 06dd15ff42b7..28f272bf9479 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/hard_bounced.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/hard_bounced.php
@@ -7,6 +7,6 @@
 $wh->setTags(["test-tag"]);
 $wh->setMetadata([]);
 $wh->setReason('Host or domain name not found');
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/opened.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/opened.php
index 8deb1ca7ceb0..3cd99248dfab 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/opened.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/opened.php
@@ -8,6 +8,6 @@
 $wh->setMetadata([
     'ip' => '127.0.0.1'
 ]);
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/opened_unique.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/opened_unique.php
index 8deb1ca7ceb0..3cd99248dfab 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/opened_unique.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/opened_unique.php
@@ -8,6 +8,6 @@
 $wh->setMetadata([
     'ip' => '127.0.0.1'
 ]);
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/sent.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/sent.php
index 519813c9a39c..ce456665d8ef 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/sent.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/sent.php
@@ -7,6 +7,6 @@
 $wh->setTags(["test-tag"]);
 $wh->setMetadata([]);
 $wh->setReason('');
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/soft_bounced.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/soft_bounced.php
index 0973e3cd637f..447c92ba9001 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/soft_bounced.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/soft_bounced.php
@@ -7,6 +7,6 @@
 $wh->setTags(["test-tag"]);
 $wh->setMetadata([]);
 $wh->setReason('Unknown reason');
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/spam_complaint.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/spam_complaint.php
index 7bd73b9fa97d..275113a9e940 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/spam_complaint.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/spam_complaint.php
@@ -6,6 +6,6 @@
 $wh->setRecipientEmail('test@example.com');
 $wh->setTags(["test-tag"]);
 $wh->setMetadata([]);
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/unsubscribed.php b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/unsubscribed.php
index 45e7a63beb16..460091131f0d 100644
--- a/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/unsubscribed.php
+++ b/src/Symfony/Component/Mailer/Bridge/MailerSend/Tests/Webhook/Fixtures/unsubscribed.php
@@ -9,6 +9,6 @@
     'reason' => 'NO_LONGER_WANT',
     'readable_reason' => 'I no longer want to receive these emails'
 ]);
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-01-01T12:00:00.000000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-01-01T12:00:00.000000Z'));
 
 return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/Resend/Tests/Webhook/Fixtures/sent.php b/src/Symfony/Component/Mailer/Bridge/Resend/Tests/Webhook/Fixtures/sent.php
index 9872c099a7c6..1dbd7eb59bc5 100644
--- a/src/Symfony/Component/Mailer/Bridge/Resend/Tests/Webhook/Fixtures/sent.php
+++ b/src/Symfony/Component/Mailer/Bridge/Resend/Tests/Webhook/Fixtures/sent.php
@@ -21,6 +21,6 @@
     ],
 ]);
 $wh->setReason('');
-$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.u\Z', '2024-04-08T09:43:09.500000Z'));
+$wh->setDate(\DateTimeImmutable::createFromFormat('Y-m-d\TH:i:s.uP', '2024-04-08T09:43:09.500000Z'));
 
 return $wh;