Can't connect using domain name

[jordy33]

Describe the bug
I have a private server. When i give the ip address "189.232.94.215" to the people that connects to the server every thing works fine and every body can connect. But when i give the domain name: jorge33.ddns.net no body can connect.

To Reproduce
Use de domain name: jorge33.ddns.net

Expected behavior

Screenshots

Operating system
Client: Mac OS
Server: Ubuntu

Version of Jamulus
3.6.2
Additional context

[hoffie]

Hmm, any chance you can get a network trace while the problem appears?
The name seems to resolve properly (although a bit slow). I tried to connect and it did not work for me, but it did not work for me using the IP directly either.
Is your server running right now?

[chrisrimple]

Is this a cloud or local server? Are you sure that you have ddns.net configured correctly? The fact that users can connect to the direct IP implies that there are no port forwarding, etc. issues, so it seems like the DNS mapping is the issue.

[jordy33]

Hmm, any chance you can get a network trace while the problem appears?
The name seems to resolve properly (although a bit slow). I tried to connect and it did not work for me, but it did not work for me using the IP directly either.
Is your server running right now?

Nope is down... I'll turn on.

[hoffie]

Nope is down... I'll turn on.

Is it still up? I still cannot connect, even using the IP.

When you or your colleague tested based on the IP, where was this person located? Were they in a different location with a different ISP/dialup/cable connection or did they share it with you (= same network)?