I've been playing for a week or two and suddenly after I finished a battle, the game would become unresponsive and tell me there was a server connection failure and to retry or relogin. This happened several times. Finally it stopped responding altogether except for the error message. I've got the latest version and have been playing on Bluestacks for Windows.  All other apps/games work fine. Is there any solution to this? I've restarted the computer, restarted Bluestacks, and nothing. I've also tried connecting by VPN.