Debug my PayPal IPN page.

Hello, I have already installed an instant download shop script on my page, all of the features work on it accept the paypal IPN notify page, all orders, including paid orders, show up as unpaid. I would like someone to go in and get this working correctly for me. I have a $30 budget to fix this script, please pmb with how soon you can start. Payment will be made once the script is up and running correctly and I have tested it. Please be formiluar with PayPal Instant Payment Notification (IPN) before accepting this project. Thank you for your time. -Dark