I am trying to release Elastic IP addresses from my AWS account.
I do not have any EC2 instances running.
When I select the EIP rows from the table in the console and click "Release Elastic IP address," I get the following error message:

The problem is that the "Disassociate Elastic IP Address" menu is grayed out, meaning I may not have any living objects to disassociate from.
From the table of Elastic IP addresses, I cannot figure out what objects may need to be removed in order to release these EIP addresses.
Thanks.
You may need to remove a network interface that's hanging around. Check to see if your elastic IP is associated with any of your network interfaces.
Here's how to check with us-east-1 as an example:
https://us-east-1.console.aws.amazon.com/ec2/home?region=us-east-1#NIC:
Change [us-east-1] to the region you use.