К сожалению не понятно что с ними не так

Есть вот такой код
<?php
if ($_SERVER["REQUEST_METHOD"] == "POST" {
// Get the form fields and remove whitespace.
$name = strip_tags(trim($_POST["name"]));
$name = str_replace(array("r","n",array(" "," ",$name);
$subjects = strip_tags(trim($_POST["subject"]));
$subjects = str_replace(array("r","n",array(" "," ",$subjects);
$email = filter_var(trim($_POST["email"]), FILTER_SANITIZE_EMAIL);
$message = trim($_POST["message"]);

// Check that data was sent to the mailer.
if ( empty($name) OR empty($subjects) OR empty($message) OR !filter_var($email, FILTER_VALIDATE_EMAIL)) {
// Set a 400 (bad request) response code and exit.
http_response_code(400);
echo "Oops! There was a problem with your submission. Please complete the form and try again.";
exit;
}

// Set the recipient email address.
// FIXME: Update this to your desired email address.
$recipient = "supportУдалён

// Set the email subject.
$subject = "New contact from $name";

// Build the email content.
$email_content = "Name: $namen";
$email_content .= "Email: $emailnn";
$email_content .= "Subject: $subjectsnn";
$email_content .= "Message:n$messagen";

// Build the email headers.
$email_headers = "From: $name <$email>";

// Send the email.
if (mail($recipient, $subject, $subjects, $email_content, $email_headers)) {
// Set a 200 (okay) response code.
//http_response_code(200);
echo "Thank You! Your message has been sent.";
} else {
// Set a 500 (internal server error) response code.
//http_response_code(500);
echo "Oops! Something went wrong and we couldn't send your message.";
}

} else {
// Not a POST request, set a 403 (forbidden) response code.
//http_response_code(403);
echo "There was a problem with your submission, please try again.";
}

?>
Нужен он для отправки сообщений с обратной формы,при отправке пишет вот такую ошибку
<br /> <b>Warning</b>: mail(): Multiple or malformed newlines found in additional_header in <b>/var/www/daffy.biz/mailer.php</b> on line <b>41</b><br /> Oops! Something went wrong and we couldn't send your message.
Что не так с кодом?