I need to create validation for this form, and I don't know how to do it right.
    <?php
$errName = '';
$errEmail = '';
$errMessage = '';
$result = '';
if (isset($_POST["submit"])) {
    $name = $_POST['name'];
    $email = $_POST['email'];
    $message = $_POST['message'];
    $from = 'simply@email.tld';
    $to = 'again@email.tld';
    $subject = 'Form';
    $body = "Name: $name \n E-mail: $email \n Message: $message";
}
if (!$_POST['name']) {
    $errName = 'Write Name here.';
}
if (!$_POST['email'] || !filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) {
    $errEmail = 'Write correct e-mail';
}
if (!$_POST['message']) {
    $errMessage = 'Write your message';
}
if (!$errName && !$errEmail && !$errMessage) {
    if (mail ($to, $subject, $body, $from)) {
        $result = "<div style='color:white;font-size:15px;font-weight:700;'>Your message has been sent.</div>";
    } else {
        $result = "<div style='color:red;font-size:15px;font-weight:700;'>Your message has not been sent, try again!</div>";
    }
}
?>
The form works right but if as example I won't write one thing there is no error, message just isn't sent. Any ideas what's wrong?
 
    