The VPN lab only supports one (1) active connection at a time. Having multiple active connections from the same machine, will cause issues to the VPN and you will be unable to start or reach machines.

Solution: "sudo killall -w openvpn" command and reconnect to the VPN again. For future occasions, in order to break the connection, you should use CTRL-C, closing the terminal or just closing the laptop/vm can leave the connection active.