can't join Japan server

My friend is from Taiwan, he always play on japan server. I'm playing aurabot for him. this year, I cannot join his hideout becaus I get disconnected. at the menu, where you can select all region servers. all region servers are working excecpt japan server. I think I am banned from Japan server. I didn't do anything wrong. Im playing the game. all i could think what triggered them because my client always crashing alot. maybe they think im ddosing their server.