Getting {$product->reference} variable in PHP

[ZENM97]

Hi all,

I'm not getting the product reference to pull through with the following code in my php script:

$data['info']['setup']['split_payment']['merchant_id'] = $product.reference;

The module is reading it as null, so not sure where I've gone wrong?

File is attached, it's line 635.

Any help or insight would be greatly appreciated!
Many thanks in advance.

payfast.php