As SuperSlimesKing mentioned before, sending the IP of a server is illegal. If someone knows about your server without you having to speak about it on the chat and wants the IP, message him through private messages, don't use the general chat to send the IP since users will most likely be curious and join your server.
I'd like to reiterate, promoting your server, someone else's server or doing any other type of advertising has a consequence.
About you not knowing that it wasn't illegal, it's not the staff's fault that you didn't take the time to read the rules of the server, even the server's chat reminds it to players quite often…
Unban Appeal Denied.