Azure DevOps: Auto-redeploy trigger (When New target is available) Not working

I'm using Azure DevOps pipeline to trigger automated release to group of servers. For this using Deployment group job.

My situation is i'm a fleet of EC2 instances grouped and managed by AWS AutoScaling group. New instance is launch with custom AMI pre-installed with required software packages and Azure build agent is installed at boot time. Now, I wan't this new instance to be installed with latest release of my application.

I have read Azure support post deployment trigger which can this job, I have verified new target become available when ASG create EC2 instance but no deployment is trigger on it.

Based on the doc: https://learn.microsoft.com/en-us/azure/devops/release-notes/2018/jul-10-vsts#automatically-deploy-to-new-targets-in-a-deployment-group, you can now configure the environment to automatically deploy the last successful release to the new targets.

It means that it will create a new Release and redeploy in new target agents with required tag if you add some new agents into Development groups and the target agents have the required tags, as followed.

I was installing Azure Agent without tag so new target is ignored for post deploy triggers. When I install Azure Agent with tag specifying my trigger executed successfully.

For Adding Tag follow this link https://learn.microsoft.com/en-us/azure/devops/pipelines/agents/v2-linux?view=azure-devops#deployment-group-only