PHP Email: No data being displayed although email is sent - php

Question

I'm using g-Recaptcha v3 to pass a hidden token and HTML "Contact" form data to form.php file on the localhost, which verifies the g-Recaptcha data, returns a default prompt to end-user and sends an email, via the localhost to the default email address.
The email received does not display data captured, via the HTML "Contact" form. I have tried changing the syntax, I have tried additional "If/Else" statements as well as adding "POST" commands without any success.
HTML contact form section:
<!-- The Contact Section -->
<div class="w3-container w3-content w3-center w3-blue-gray w3-padding-64" style="max-width:1400px" id="contact">
<div class=" w3-container w3-content w3-center" style="max-width:1000px">
<h2 class="w3-wide">Contact</h2>
<p class="w3-opacity"><i>~ Lets Talk About Your Current Needs ~</i></p>
<form id="comment_form" action="form.php " method="post" target="_blank" >
<input class="w3-input w3-border w3-text-gray w3-center" type="text" placeholder="Enter Your First Name: ex. Mark (with no spaces, punctuations or symbols)" name="fname" maxlength="32" pattern="[A-Za-z]{1,32}" required><br>
<input class="w3-input w3-border w3-text-gray w3-center" type="text" placeholder="Enter Your Last Name: ex. Wilson (with no spaces, punctuations or symbols)" name="lname" maxlength="32" pattern="[A-Za-z]{1,32}" required>
<input class="w3-input w3-section w3-border w3-text-gray w3-center" type="text" placeholder="Enter Your Email: ex. yourname#domainname.com" name="email" pattern="^([a-zA-Z0-9_\-\.]+)#((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$" required>
<input class="w3-input w3-section w3-border w3-text-gray w3-center" placeholder="Enter Your Phone Number: ex.[phone] or 1121121112" name="phone" pattern="^(\s*)?(\+)?([- _():=+]?\d[- _():=+]?){10,14}(\s*)?$" required>
<textarea class="w3-input w3-section w3-border w3-text-gray w3-center" placeholder="Please Place Your Comment Here" name="comment" rows="5" required></textarea>
<i class="fa fa-paper-plane-o"></i>
<input type="submit" name="submit" value="SEND MESSAGE" class="w3-text-black"><br><br>
</form>
<script>
// when form is submit
$('#comment_form').submit(function() {
// we stopped it
event.preventDefault();
var fname = $('#fname').val();
var lname = $('#lname').val();
var email = $('#email').val();
var phone = $('#phone').val();
var comment = $("#comment").val();
// needs for recaptacha ready
grecaptcha.ready(function() {
// do request for recaptcha token
// response is promise with passed token
grecaptcha.execute('----------My Public Key----------', {action: 'create_comment'}).then(function(token) {
// add token to form
$('#comment_form').prepend('<input type="hidden" name="g-recaptcha-response" value="' + token + '">');
$.post("form.php",{fname: fname, lname: lname, email: email, phone: phone, comment: comment, token: token}, function(result) {
console.log(result);
if(result.success) {
alert('Thanks for posting your comment!')
} else {
alert('Spammed Message - This Process Will Be Terminated')
}
});
});;
});
});
</script>
form.php
<?php
$fname;$lname;$email;$phone;$comment;$captcha;
if(isset($_POST['fname'])){
$fname=$_POST['fname'];
}if(isset($_POST['lname'])){
$lname=$_POST['lname'];
}if(isset($_POST['email'])){
$email=$_POST['email'];
}if(isset($_POST['phone'])){
$phone=$_POST['phone'];
}if(isset($_POST['comment'])){
$comment=$_POST['comment'];
}if(isset($_POST['token'])){
$captcha=$_POST['token'];
}
if(!$captcha){
echo '<h2>Please check the the captcha form.</h2>';
exit;
}
$secretKey = "--------------My Secret Key-----------------";
$ip = $_SERVER['REMOTE_ADDR'];
// POST REQUEST TO SERVER
$url = 'https://www.google.com/recaptcha/api/siteverify?secret=' . urlencode($secretKey) . '&response=' . urlencode($captcha);
$response = file_get_contents($url);
$responseKeys = json_decode($response,true);
header('Content-type: application/json');
if($responseKeys["success"]) {
echo json_encode(array('success' => 'true'));
} else {
echo json_encode(array('success' => 'false'));
}
// COLLECT CONTACT FORM DATA
$email = $_POST['email'];
$fname = $_POST['fname'];
$lname = $_POST['lname'];
$number = $_POST['phone'];
$comment = $_POST['comment'];
// FORMAT EMAIL
$to = "default#emailaddress.com";
$headers = "From: {$to} \r\n";
$headers .= "Reply-To: {$email } \r\n";
$subject = "New form submission ... \r\n";
$body = "First Name: {$fname} \r\n";
$body .= "Last Name: {$lname} \r\n";
$body .= "Email: {$email} \r\n";
$body .= "Phone: {$phone } \r\n";
$body .= "Comment: {$comment}";
// SEND EMAIL to DEFAULT RECIPIENT VIA LOCALHOST
$send = mail($to, $subject, $body, $headers);
?>
HTML contact form:
Google g-recaptcha v3 verification prompt:
Email, via contact form, with missing data: