Discovery ec2 for elasticsearch 7.4.2

Hi,

I'm trying to setup elasticsearch cluster on ECS on AWS. I'm able to start 3 elasticsearch nodes, each on separate host but I'm not able to connect those instances to one cluster. I've checked https://medium.com/@devfire/deploying-the-elk-stack-on-amazon-ecs-dd97d671df06 this tutorial and everything works perfectly but it's for version 5.6.4, when I tried it with 7.4.0 or 7.4.2 it doesn't work. I went through discovery ec2 plugin documentation and I've updated the elasticsearch.yml file but it still does not work.

Here my lastest elasticsearch.yml file:
cluster.name: "elasticsearch"
node.name: ${HOSTNAME}
network.host: eth0
http.port: 9200
transport.port: 9300
network.publish_host: ec2:privateIp
transport.publish_host: ec2:privateIp
discovery.zen.minimum_master_nodes: 2
discovery.seed_providers: ec2
bootstrap.memory_lock: false
discovery.ec2.endpoint: ec2.eu-west-1.amazonaws.com
discovery.ec2.tag.ElasticSearch: nonprod
discovery.ec2.availability_zones: eu-west-1a,eu-west-1b,eu-west-1c
cluster.routing.allocation.awareness.attributes: aws_availability_zone
discovery.ec2.host_type: private_ip

With this setup I was able to start 2 docker containers on one host and they connected to one cluster, but the idea is that we want to have elasticsearch node per host.

Any ideas what is wrong?