AWS ELB Configuration not working on Tower Cluster

I am using AWS ELB to act as proxy server in front of my Ansible Tower cluster.

While trying to access ELB DNS name I am getting "This site can’t be reached" Error message. Also "tower-elb-********.us-east-1.elb.amazonaws.com refused to connect." message .

I have installed ansible tower as below:
./setup.sh -i inventory -e nginx_disable_https=1

Post installation I have updated "custom.py" file under /etc/tower/conf.d.
Added ::
SESSION_COOKIE_SECURE = False
CSRF_COOKIE_SECURE = False

and also made changes to "REMOTE_HOST_HEADERS" as below ::
REMOTE_HOST_HEADERS = ['HTTP_X_FORWARDED_FOR', 'REMOTE_ADDR', 'REMOTE_HOST']

Post making all the above changes I restart ansible tower on all nodes.

Please note I am able to login to each ansible tower node without any issues, but not able to login through AWS ELB.