Bukkit server wont work after I failed making a bungee cord server

Yesterday my server was working fine, I had my friends join and it was great. Later i felt the need to make my bukkit server a bungee cord server, I failed making it so I got rid of it, after that I noticed it wasn't letting my friends join. The logs are still fine. There using the right ip but it says they can't resolve the host name. So I decided to get rid of the server and make a new one they still couldn't join the bukkit server. The thing that's making me go crazy though is the fact that they can join me on a regular vanilla server.

 

You may have the incorrect config in your server.properties, send it to me and I will have a look at it for you. Do you still want Bukkit, or BungeeCord as well? (Plus, check if you forwarded all the ports needed)
@Okalmix