You can consult the game customer service or pay attention to the game official website.
Server acquisition failed, which may be caused by network or server.
If the network is not good, you will usually get a hint of server failure.
Another possibility is the back-end service of the website, which is a developer's problem. It's not the user's problem, it's not the user's problem
Chivalrous version includes BOSS map, armor and other armor and overlord cards that can be upgraded to level 5, and adds the first and second martial arts such as nightmare Sirius sword and heavenly magic sword.