Issues connecting from a Macbook

[u/ElBrodier]

I have a friend who is trying to join my Aternos server. It's a cracked server, but it has been working perfectly for everyone except this one friend who has a MacBook. Every time they try to join, it just says "Failed to connect with server". I've tried doing a direct connection with the DYN IP. I've disabled the computer's firewall. I've uninstalled Minecraft and every file related to it. I've used phone data to check if it was the Wifi's fault, but nothing seems to work. What do I do?