Elastic IP disconnects from Beanstalk

We have a PHP application running on Elastic Beanstalk and Elastic IP.

It is mostly running correctly, but from time to time the Elastic IP gets disconnected from the Beanstalk. We checked Beanstalk events the last time it happened - there was an environment update and new instance was added to load balancer and then to the environment. I'm not sure this is the reason for disconnection, but nothing else happened at that date.

Deploying the new version doesn't cause Elastic IP to disconnect, there is a restart of instances as well, so I'm not sure what it is causing exactly.

Does anybody have some hint what can be done to ensure that elastic IP doesn't get disconnected?