Nefunkční kontrola formuláře

<?php
if (isset($_POST['submit'])){
    if (!empty($_POST['old_pass'])){
        $old=$_POST['old_pass'];
    }    
    else{
        echo "Nezadal jste staré heslo";
        echo "<br>";
    }
    
    if (!empty($_POST['new_pass'])){
        $new=$_POST['new_pass'];
    }    
    else{
        echo "Nezadal jste nové heslo";
        echo "<br>";
    }
    
    if (!empty($_POST['new_pass1'])){
        $new1=$_POST['new_pass1'];
    }    
    else{
        echo "Nezadal jste kontrolní heslo";
        echo "<br>";
    }
    if ($new == $new1){
        $pass=$new;
    }
    else{
        echo "Hesla se neschodují";
        echo "<br>";
    }
}
else{
echo"<form method='post' action='#' name='edit_pass'>";    
echo"<table>";
echo"<tr><td>Staré heslo:</td><td><input type='text' name='old_pass' size='44'></td></tr>";
echo"<tr><td>Nevé heslo:</td><td><input type='text' name='new_pass' size='44'></td></tr>";
echo"<tr><td>Znovu:</td><td><input type='text' name='new_pass1' size='44'></td></tr>";
echo"<tr><td><input type='submit' name='submit' value='Změnit'></td></tr>";
echo"</table>";
echo"</form>";
} 
?>