Nginx scoket.io在前端发送操作码-1并断开客户端的连接

我有两个ec2实例，它们通过aws应用程序负载平衡器连接。我的nginx套接字配置如下：

location ~* \.io {
  proxy_set_header X-Real-IP $remote_addr;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  proxy_set_header Host $http_host;
  proxy_set_header X-NginX-Proxy true;

  proxy_pass http://localhost:3000;
  proxy_redirect off;

  proxy_http_version 1.1;
  proxy_set_header Upgrade $http_upgrade;
  proxy_set_header Connection "upgrade";
}

现在发生的是，当客户端尝试连接时，它给出操作码-1并断开连接

它还为url

ws://url.com/socket.io/？EIO=3&transport=websocket&sid=3qrukUCAjUPKRBlfAAAn提供了400个错误的请求