Unable to send mail using Html PHP - php

Question

I am creating a website and I was making a appointment form with PHP. It is turning up no errors on the page itself but the email never shows up in the inbox or spam folder of my email. The code I have for it is:
`
<form action="contact.php" method="POST">
<div class="row g-3">
<div class="col-12 col-sm-6">
<select name="Doctor" class="form-select bg-light border-0 mb-3" style="height: 55px;">
<option selected>Select A Doctor</option>
<option value="PROF DR AZFAR FAROGH">PROF DR AZFAR FAROGH (MEDICINE)</option>
<option value="PROF DR AJWAD FAROGH">PROF DR AJWAD FAROGH (CARDIAC SURGERY)</option>
<option value="PROF DR IRFAN KHAN">PROF DR IRFAN KHAN (HEMATOLOGY)</option>
<option value="DR ASMA HASSAN">DR ASMA HASSAN (PULMONOLOGY)</option>
<option value="DR USAMA MUNIR">DR USAMA MUNIR (CARDIOLOGY)</option>
<option value="DR AWAIS NIZAMI">DR AWAIS NIZAMI (CARDIOLOGY)</option>
<option value="DR SUMYYA ASHRAF">DR SUMYYA ASHRAF (FAMILY PHYSICIAN)</option>
<option value="DR SABAHAT GUL">DR SABAHAT GUL (CARDIOLOGY)</option>
<option value="DR MUHAMMAD BURHAN BARKAT">DR MUHAMMAD BURHAN BARKAT (UROLOGY)</option>
<option value="DR MADIHA AZHAR">DR MADIHA AZHAR (DERMATOLOGY)</option>
<option value="DR FAHAD QAISAR">DR FAHAD QAISAR (MEDICINE)</option>
<option value="DR MAHTAB AHMED MUKTAR PATAFI">DR MAHTAB AHMED MUKTAR PATAFI (PHYSIOTHERAPY)</option>
<option value="DR NASIR MAHMOOD">DR NASIR MAHMOOD (PHYSIOTHERAPY)</option>
<option value="DR SHEHR BANO">DR SHEHR BANO (PHYSIOTHERAPY)</option>
<option value="DR MUHAMMAD WASSAM">DR MUHAMMAD WASSAM (PHYSIOTHERAPY)</option>
<option value="DR SARAH NISAR">DR SARAH NISAR (RADIOLOGY)</option>
<option value="DR SARAH NISAR">DR AHMAD BILAL (RADIOLOGY)</option>
<option value="DR ZAFAR JAM">DR ZAFAR JAM (CARDIOLOGY)</option>
<option value="DR ANWAAR UL HASSAN">DR ANWAAR UL HASSAN (CARDIOLOGY)</option>
<option value="DR JUNAID AKHTER">DR JUNAID AKHTER (CARDIOLOGY)</option>
<option value="DR M ZUBAIR AHMAD">DR M ZUBAIR AHMAD (PEDIATRIC SURGERY)</option>
<option value="DR GOHAR BASHIR">DR GOHAR BASHIR (CARDIAC SURGERY)</option>
</select>
</div>
<div class="col-12 col-sm-6">
<input type="text" name="Name" class="form-control bg-light border-0" placeholder="Your Name" style="height: 55px;" required>
</div>
<div class="col-12 col-sm-6">
<input type="email" name="Email" class="form-control bg-light border-0" placeholder="Your Email" style="height: 55px;" required>
</div>
<div class="col-12 col-sm-6">
<input type="number" name="Number" class="form-control bg-light border-0" placeholder="Your Phone Number" style="height: 55px;" required>
</div>
<div class="col-12 col-sm-6">
<input type="number" name="CNIC" class="form-control bg-light border-0" placeholder="Your CNIC Number" style="height: 55px;" required>
</div>
<div class="col-12 col-sm-6">
<SELECT name="Gender" class="form-control bg-light border-0" placeholder="Select Your Gender" style="height: 55px;" required>
<option name="MALE">MALE</option>
<option name="FEMALE">FEMALE</option>
<option name="NEUTER">NEUTER</option>
</SELECT>
</div>
<div class="col-12 col-sm-6">
<input type="number" name="AGE" class="form-control bg-light border-0" placeholder="AGE" style="height: 55px;" required>
</div>
<div class="col-12 col-sm-6">
<div class="date" id="date1" data-target-input="nearest">
<input type="text" name="Date" class="form-control bg-light border-0 datetimepicker-input" placeholder="Appointment Date" data-target="#date1" data-toggle="datetimepicker" style="height: 55px;" required>
</div>
</div>
<div class="col-12 col-sm-6">
<input type="text" name="Comments" class="form-control bg-light border-0" placeholder="Additional Comments" style="height: 55px;">
</div>
<div class="col-12">
<button class="btn btn-dark w-100 py-3" type="submit">Make Appointment</button>
</div>
</div>
</form>
this is my php file:
<?php
header("Location: ../appointment.html");
if(isset($_POST['Name']) &&
isset ($_POST['Email']) &&
isset ($_POST['Doctor']) &&
isset ($_POST['CNIC']) &&
isset ($_POST['Number']) &&
isset ($_POST['Gender']) &&
isset ($_POST['Age']) &&
isset ($_POST['Date']) &&
isset ($_POST['Comments'])) {
$Name = $_POST['Name'];
$Email = $_POST['Email'];
$Doctor = $_POST['Doctor'];
$CNIC = $_POST['CNIC'];
$Number = $_POST['Number'];
$Gender = $_POST['Gender'];
$Age = $_POST['Age'];
$Date = $_POST['Date'];
$Comments = $_POST['Comments'];
$to = '********#gmail.com';
$subject = 'Appointment' . $name;
$body = $message;
$headers = 'From:' . $email . "\r\n" . "CC: ********#gmail.com";
if (mail($to, $subject, $body, $headers)) {
echo 'your message has been sent!';
} else {
echo 'There was an error sending your message.';
}
}
?>
I tired sending just name and message ,it worked but then i tired on this form ,it doesn't worked.