Everyone except for one of my friends can join my minecraft server hosted through playit

I am hosting a private Minecraft server for me and my friends. Everyone is able to join except one friend. I had the same issue when trying to host a Palworld server as well where everyone could join except him. Does anyone know how to fix this? We all live in relatively the same area so I don’t think location should be causing any issues.

ask him to do ping and telnet from his PC going to your server

This issue is now on the ISP of your friend

It is possible that the ISP of your friend blocks connections from playit.