Hello, how are you ???, I’ve seen your simple IPN code for PayPal
https://github.com/kidino/simple-ipn
https://github.com/kidino/simple-ipn
I write here, since I don’t see a contact mail in Github.
I have been able to configure it for my PayPal account, but there are things that I don’t know how to configure.
The purchase button works for me, but I don’t know how to access the download file once the payment is made.
I do the tests with Sandbox, I already have the IPN activated.
Assuming that the URL of my website is …..   https://www.myweb.com/buydownload.html
I could make a small example of a simple website with a button, To download the MP3 file ?? and explain a little the operation of the code ??
My mail is tolo68cs@gmail.com
Thank you very much and have a good day.