Mail script won't send every field - php

Question

Sorry for the stupid question (I'm just starting out) but I can't quite understand why the phone field of my PHP script won't appear in the email I receive. I've added the field in HTML in works fine, the error message if the phone field is empty works good but if I run it, the email I receive will not contain the field.
Here is the PHP mail script:
<?php
require('email_config.php');
// sender information
$name = trim($_POST['name']);
$phone = trim($_POST['phone']);
$email = trim($_POST['email']);
$message = trim($_POST['message']);
$error = "";
// check sender information
$pattern = "^([a-zA-Z0-9_\-\.]+)#((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$^";
if(!preg_match_all($pattern, $email, $out)) {
$error = $invalid_email; // for invalid email
}
if(!$email) {
$error = $invalid_email; // for empty email field
}
if (!$phone) {
$error = $invalid_phone; // for empty phone field
}
if(!$message) {
$error = $invalid_message; // for empty message field
}
if (!$name) {
$error = $invalid_name; // for empty name field
}
// email header
$headers = "From: ".$name." <".$email.">\r\nReply-To: ".$email."";
if (!$error){
// sending email
$sent = mail($to_email,$subject,$message,$headers);
if ($sent) {
// if message sent successfully
echo "SEND";
} else {
// error message
echo $sending_error;
}
} else {
echo $error; // error message
}
?>
Thanks in advance!

Answer 1

Looks like you skipped adding the phone to the message, Your message
should be something like this
$message = trim($_POST['message']).' \n Phone: '.trim($_POST['phone']);
Seems like you are sending with plan text email so i used the new line special character /n.
To learn more about the special string characters
http://www.php.net/manual/en/language.types.string.php#language.types.string.syntax.single