Not sure; PHP or System Error

Hello. I am trying to send mail to outside people using a contact form on a website. It sends, but nothing is being retrieved. This is my code, it does goto the mailsent confirmation link, so I am guessing it sends. The maillog says this as well

PHP Code: <?php

if (isset($_POST[‘submit’])) {
$name = $_POST[“name”];
$mailFrom = $_POST[“email”];
$message = $_POST[“message”];
$mailTo = “the-email@being-sentto.com”;
$headers = "From: ".$mailFrom;
ini_set(“sendmail_from”, $mailFrom);
$txt = "You have received an email from “.$name.”.

".$message;
mail($mailFrom, $mailTo, $headers, $txt);
header(“Location: index.html?mailsent”);
}
Maillog Log:
Nov 24 05:29:39 myrealdomain postfix/smtpd[253323]: connect from myrealdomain.com[127.0.0.1]
Nov 24 05:29:39 myrealdomain postfix/smtpd[253323]: NOQUEUE: reject: RCPT from myrealdomain.com[127.0.0.1]: 550 5.1.1 root@myrealdomain.com: Recipient address rejected: User unknown in virtual mailbox table; from=root@myrealdomain.com to=root@myrealdomain.com proto=ESMTP helo=<myrealdomain.com>
Nov 24 05:29:39 myrealdomain postfix/smtpd[253323]: NOQUEUE: reject: RCPT from myrealdomain.com[127.0.0.1]: 550 5.1.1 root@myrealdomain.com: Recipient address rejected: User unknown in virtual mailbox table; from=<> to=root@myrealdomain.com proto=ESMTP helo=<myrealdomain.com>
Nov 24 05:29:39 myrealdomain postfix/smtpd[253323]: NOQUEUE: reject: RCPT from myrealdomain.com[127.0.0.1]: 550 5.1.1 postmaster@myrealdomain.com: Recipient address rejected: User unknown in virtual mailbox table; from=<> to=postmaster@myrealdomain.com proto=ESMTP helo=<myrealdomain.com>

I should add that it does send out externally from my MS Outlook client. and I am also able to retrieve it that way. But the web form just does not want to operate. Also, I don’t have a postmaster or a root@mydomain. The email that is coming from is admin, and that name is setup for email. Can someone please help? Thank you!