Getting Pool is now shutting down message from akka when using SNS publish from my application

I have a few streams that wake every min or so and pulling some docs from the DB and performing some actions and in the end sending messages to SNS.

the tick interval is every 1 min currently.

every few minutes I see this error info in the log:

[INFO] [06/04/2020 07:50:32.326] [] [default/Pool(shared->] Pool is now shutting down as requested.

[INFO] [06/04/2020 07:51:32.666] [] [default/Pool(shared->] Pool shutting down because triggered after 30 seconds.

in not sure what that means…does someone had it before? 443 was worrying me.