Nostalrius Begins - Quality wow vanilla realm (1.12)

I am from Russia and recently i have moved to Serbia with my family. Few days i have been playing wow here normaly. This morning when i tried to log in there is a message saying:"This account is closed". No explanation or anything. I can still log in to nostalrius site and on account page it says: "enjoy your stay".
Can someone please explain me What is wrong here? What have i done? Why is my account closed without explanation? My character name is lvl 60 gnome warlock named Pyroboom. Please assist me with this.
Regards.

If there is any additional information you would need to restore my account just ask. I am here.

Hello nostalrius staff!
Just want to say thanks for assisting me with my problem. My account access is restored. You gyes are awesome!
Thank you again!