prob w/datediff

Hi guys, please advise me as to what I'm doing wrong. My test database table fields have
"payrec" has 'p', "amtdue" is blank, recur has 'N' and "duedate" is past.
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the code:

<html><head>
<style>
@page { size 8.5in 11in; margin: 2cm }
div.page { page-break-after: always }
</style>
</head><body><center>
<div class="page">

<?php
//Open a new connection to the MySQL server
require_once "getacctdb.php";

//MySqli Select Query
$results =…

prob w/datediff