After ready this https://s2member.com/kb-article/building-an-api-notification-handler-webhook/
I am using stripe as a payment gateway only.
I followed exactly the same procedure in the url i insert(changed ip here for security reason) http://1.2.3.123:49005/SingleMethodName=DomainManagementStripeService___DomainRegistration?s2_payment_notification=yes&user_id=%%user_id%%&item_number=%%item_number%%
and in the mu-plugins the same code copy-paste.
I receive nothing. Yes emails are sent out correctly. Yes my server is receiving any type of request on each time you call this url. Any idea why is it not sending the user data to url? Thanks