How to update AAACertificateServices on server to send apns?

Question

On March 29, 2021, token and certificate-based HTTP/2 connections to the Apple Push Notification service must incorporate the new root certificate (AAACertificateServices 5/12/2020) which replaces the old GeoTrust Global CA root certificate. To ensure a seamless transition and to avoid push notification delivery failures, verify that both the old and new root certificates for the HTTP/2 interface are included in the Trust Store of each of your notification servers before March 29.

Note that Apple Push Notification service SSL provider certificates issued to you by Apple do not need be to updated at this time.

I got this email regarding the updation of push notification certificates. I am not using any third party service to send apns. I have write PHP script to send notification. previously the same PHP script sent notification but now it's not working. It shows message like Notification sent successfully but notification did not deliver. Here is my question about sending notification using PHP Script APNS not deliver to device.

Please update how to sent notification using php or what to do on server side to manage AAACertificateServices

Thanks