How can I unsubscribe the one that I'm billing?

The $3.72 charge on your AWS bill is from a public IPv4 address being used in the Seoul region. To stop the charges, you can either release the Public/Elastic IP (if you're not using it) or stop or terminate the resoure, like an EC2 instance or NAT Gateway that's using it. You can find and manage these in the EC2 Console dashboard. Also, check for any idle network interfaces or NAT gateways that might be active.

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