If you are not the owner of the server then I have bad news. It is up to the server owner to fix this. You can try to e-mail them, let them know and see if it is getting fixed. It might be the whole server or it might just be the chunks that you are in, though I believe it is the former as you obviously did not place any Secret Room blocks according to yourself. Hopefully the owner of the server will reply that it is getting fixed. Here is hoping it is not too long to wait.