unexpected disconnection when enter new maps

i got an unexpected disconnection when i enter new maps which i have never done before. I tried to restart the game-pc and change sever but not works.

I and my sons are having the same issue. Its only some maps and there seems to be no obvious reason for it. Loaded up a Kirak Map and it refused to let either of us into the map. We get booted back to login screen with unexpected error occurred. Loaded a different map and it works. Its hit or miss and really frusterating.