Ticket wasn’t deliverd

Do you mean that the customer received an email from your site, but it didn’t contain a link to the ticket, or do you mean that the customer received a confirmation from your payment gateway, but not from your site?

Hello, the customer received a confirmation and receipt from my payment gateway, not from my site.

Can you confirm whether the email was sent from your site? It would have been logged in the Payment Record for that purchase at My Tickets > Payments.

Hello, here is the screenshot for the purchase information. (https://i.imgur.com/HovHveY.png)

The status is still pending but I already received the payment.

The receipt that my client received. (https://i.imgur.com/QEiVLRX.png)

OK. Do you have IPN enabled in your PayPal account?

Yes, it is enabled.

Attached is what I see in my PayPal IPN history. (https://i.imgur.com/rpCbee8.png)

If you view the IPN record, what is the HTTP code of the attempted message?