When I try to grt in the server my game tells me "An existing connection was forcibly closed by the remote host" how do I fix it and if I am band can someone please lift it. 

I know it's a google search, but this may help google search

If you are banned you would see a “you are banned” sort of page

You need to update your version of forge to 14.23.5.2857 or higher

It can be downloaded from here: https://files.minecraftforge.net/net/minecraftforge/forge/index_1.12.2.html

 ok now I'm band

Anyone know a Joee3

ok so apparintly I found a nether portal and I go in and I spawnd in a maze an I did not find a way out so dug down to kill my self and I did four days later (at this point I can't get in the server) I got band so can someone please lift it 

You were banned for griefing blocks under my city, if you wish to appeal the ban, you can do so in the relevant forums category using the correct format