Can't use chat, Perma muted ?

Hello, When i’m playing on mapeadores zombie escape server, I cannot write to the chat, when I enter a text nothing happens, like i’m muted. I rarely play on this server and I almost never used the chat or just to say basics commands like “rtv”. But now I can’t rtv or enter others commands. Can an admin try to solve the problem ?

IGN : Edger-Sama

Thanks.