the email is using a column form the recordset. The recordset is filtereed on a querystring variabale that does not exist when the form is posted, causing the recordset to be empty.
change the forms action:
<form action="" method="post" name="WADADeleteForm" id="WADADeleteForm">
to:
<form action="<?php echo((isset($_SERVER["PHP_SELF"]))?$_SERVER["PHP_SELF"]:"") ?>?OrderID=<?php echo(isset($_GET['OrderID'])?$_GET['OrderID']:""); ?>" method="post" name="WADADeleteForm" id="WADADeleteForm">