Earlier I created two instances of my microserice running on EC2 in us-east-1c AZ & created a classic load balancer in the same AZ – that worked smoothly.

But when I changed the AZ for the classic load balancer (created a new one in some other AZ), it threw Instance is in the EC2 Availability Zone for which the load balancer is not configured to route traffic to. despite having Cross-zone load balancing ON