Banned from my own server?

Okay, so the night before I made a server (LAN) and today, I made another… it was ZombieRP 3.4, and it played fine. I tried to start another one, and it said that my steamid, was banned! If anyone has insight on this or has had it happen to themself, I request your help, I really wanna have a server on Garry’s Mod.