Hi I never actually found an official solution for this. I had to use a workaround. Bascially, I used the custom variable. If you are already using the custom variable for something else you can use PHP explode to extract seperate values. For example I was already using custom for a Customer ID value so I had this is in my form: <input type="hidden" name="custom" value=“100”> To also add the discount amount to the custom variable I just added a colon and then the discount amount after the customer ID: <input type="hidden" name="custom" value=“100:50”> E.g. Customer ID is 100, discount amount is 50, seperated with a colon. Then when the values are posted back to your notify script you can use something like this: $custom = $_POST['custom'];
$explode = explode(":", $custom);
$customer_id = $explode[0];
$discount_amount = $explode[1]; Hope this helps. Maybe not perfect but it worked for me.
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