I set up a simple php contact form. It is working so far, I get the emails, that is not the issue. The only thing that is not working, is the "From" and "Reply-To" field. The email I receive is from www-data@hostname.com and it also replies to that address. I don't know what I might have overlooked :(
<?php
$vorname = $_POST['vorname'];
$nachname = $_POST['nachname'];
$email = $_POST['email'];
$phone = $_POST['phone'];
$club = $_POST['club'];
$handicap = $_POST['handicap'];
$spieler = $_POST['spieler'];
$bemerkungen = $_POST['bemerkungen'];
$from = 'Von: Kontaktformular'; 
$to = 'edited for this question'; 
$subject = 'Anmeldung';
$body = "Von: $vorname $nachname\n E-Mail: $email\n Telefon: $phone\n Club: $club\n Handicap: $handicap\n Spieler: $spieler\n Bemerkung: $bemerkungen ";
$headers .= "MIME-Version: 1.0" . "\r\n";
$headers .= "Content-type: text/html; charset=iso-8859-1" . "\r\n";
$headers .= "From: $email" . "\r\n" .
  "Reply-To: $email" . "\r\n" .
  "X-Mailer: PHP/" . phpversion();
if(!isset($_POST['submit'])) {
if (mail ($to, $subject, $body, $from)) {
    header("Location: edited.html"); 
} else { 
    header("Location: edited.html"); 
}
}
?>
Thanks for any hint!