Paysystems and Updating Database Subscriptions

Hello All.

Today I found out that my subscriptions to PaperNerd.com were not being updated correctly in my database, and that paying customers were being denied access to my site.

I use PaySystems.com who allows you to add fields to your payment form and return these fields (variables) to a script for further processing. They also state:

"The following is a list of all the variables that we pass to the redirect URL that you specify, and the method (POST or GET) that you have selected using the input variables."

In this list, the user-defined ones are listed as:
option1
option2
.....

So I added two fields to my form 'username' and 'password', of which I assume would have data stored in 'option1' and 'option2' respectively.

They also state that there is a field "cc_status" which is always set to 'pass' if the transaction went through properly.

So, I wrote a script (in php) that says:

if ($cc_status=="pass")
{

$query = "INSERT into my_db (username, password, pay)
VALUES ('$option1', '$option2', '$cc_status')";
result = mysql_query($query);

}

which does nothing.

Do anyone have a site that depends on whether or not the transaction has been approved using paysystems?

Thanks in advance for your time.