Submission form made with php is running into issues [duplicate]

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• PHP mail function doesn't complete sending of e-mail 27 answers

So my php code worked fine for months on end. It was set up to receive requests through spiceworks and now the the submission form will show it submitted but our IT team does not receive any emails anymore.

 <?php

if (isset($_POST['submit'])) {
$host = "ssl://smtp.example.com";
$name = $_POST['name'];
$subject = $_POST['subject'];
$mailFrom = $_POST['email'];
$message = $_POST['message'];
$mailTo = "ithelpdesk@example.com";
$headers = "From: ".$mailFrom;
$txt = "You have received an e-mail from ".$name.".\\n\\n".$message;

mail($mailTo, $subject, $txt, $headers);
header("Location: helpdesk.php?mailsend");

}

the "Example" is switched out with personal info. but the code was working fine and then just stopped. would love any guidance as i am very new to php and coding.