Not able to connect robots from AWS env to cloud orchestrator

Hi
I have two ec2 (free tie) windows server instances which I wanted to add as robots, I gave the machine name and orchestrator URL in robot settings.
It shows as connected, unlicensed in both machines.

I enabled 443 port for ingress traffic from security group settings, but from orchestrator page the robots are still showing as Disconnected. Please let me know if I missed anything.

FYI
Both machines are added as standard machines, and attended robots as community edition supports 2 attended and 1 unattended