EC2 - Known Issue - Terminated instance appears to relaunch

Solution:

Some services allow you to configure resources to auto-launch instances to replace terminated instances, which is usually done to improve the fault tolerance of an application. For example, an Auto Scaling group can be configured to launch an instance to replace an instance that is undergoing maintenance, and AWS Elastic Beanstalk environments usually include Auto Scaling groups by default.

Terminating the Auto Scaling group or Elastic Beanstalk environment will prevent replacement instances from re-launching.

To delete Auto Scaling groups, see Delete the Auto Scaling Group.

To terminate an Elastic Beanstalk environment, follow the instructions at Terminate an Environment.