PHP-General - Cookie to Form

Ok I'm new, and not a PHP person.

I have a form I'm trying to submit with cookie values or url values. The URL values are going through without a hitch but for some reason the cookie values are only working now and then. For some strange reason.

see code. note this is in a joomla module hense the script tags.

<input maxlength="100" name="LEADCF7" type="hidden" value="
{source}
<?php
if($_GET['utm_source'] != ""){
echo $_GET['utm_source'],' | ', $_GET['utm_medium'];}
else{
echo $_COOKIE['tpsource'],' | ', $_COOKIE['tpmedium'];
}
?>
{/source}
"/>

<input type="hidden" maxlength='100' name='LEADCF8' value="
{source}
<?php
if($_GET['utm_source'] != ""){
echo $_GET['utm_campaign'];}
else{
echo $_COOKIE['tpcampaign'];}
?>
{/source}
"/>

First I would write something into the page to try and diagnose if the problem is with the cookie or returning the value from the cookie.

Elsewhere in the page you could use something like, isset(); to check if the value of the cookie is set properly. Is the cookie returning a value?