Requests don't route to Primary chat-server

• Agent and customer are connected with Primary chat-server
• -Chats are active
• -Down the Primary chat-server
• Requests are being handled by chat-server B 
• Up the Primary chat -server
• Now requests  don't route to chat server A  

I waited for 3-4 minutes during the time I was doing the changing agent's state frequently.I have tested this issue two times with rizwan.mahmood