I have this droplet that can be accessed remotely using the IP (and also name). I have an ssh server listening on port 10000. I also have the standard ssh running on port 22.

When I am connected on the standard ssh (22) using the terminal, I can connect to the ssh on port 10000 with:
ssh someuser@localhost -p 10000

I have also opened the port 10000 on the firewall:
sudo ufw status

…
10000/tcp ALLOW Anywhere

10000/udp ALLOW Anywhere

…

10000/tcp (v6) ALLOW Anywhere (v6)

10000/udp (v6) ALLOW Anywhere (v6)

…

I do not have an external firewall on DO

If I try to connect using the standard ssh server:
ssh someuser@dropletiphere
I connect without problems

Problem: When I try to connect from a remote machine:
ssh someuser@dropletiphere -p 10000
I get connection refused

Is there another firewall??

UPDATE:
It turns out that it was the ssh config: The ssh server on port 10000 is a SSH tunnel, and needed to allow PortForwarding on the sshconfig file