change line 127:
$WA_redirectURL = "acclients_results.php?ClientID=".((isset($_POST["WADADeleteRecordID"]))?$_POST["WADADeleteRecordID"]:"") ."";
to:
$WA_redirectURL = "acclients_results.php?AccountantID=".((isset($_GET["AccountantID"]))?$_GET["AccountantID"]:"") ."";