Before you complete your for
looping you have echo table
close tag.
It has to be like as below.
echo "<tr><th colspan=2>Conversation</th></tr>\n";
foreach($results as $result){
$from = $result['messageFrom'];
$to = $result['messageTo'];
$message = $result['message'];
$messageID = $result['messageID'];
echo "<tr>\n";
if ($from == $messageFrom){
echo "<td><div><p>$messageFrom</p>$message</div></td>";
}
else {
echo "<td><div><p>$messageTo</p>$message</div></td>";
}
echo "</tr>\n";
}
echo "</table>";
}