Unable to GUI or SSH into Machines.

Failed to connect to remote access server. If you've just powered on your lab environment, please try again in a few minutes.

This is the Error message I get whenever I try to SSH or GUI login into a Machine I have inside a lab.
I am able to connect to the machines with the vpn/public IP setup/ but unable to get the browser based Guacamole Login screen.

This Happens only with one Lab, My other lab is working fine.

I tried Rebooting the Lab.