aws ec2 modify-ebs-default-kms-key-id \
--kms-key-id alias/aws/ebs
OR Disable default EBS Encryption:
aws ec2 disable-ebs-encryption-by-default
aws kms disable-key --key-id $KMS_KEY_ID
aws kms schedule-key-deletion \
--key-id $KMS_KEY_ID \
--pending-window-in-days 7
aws kms delete-alias --alias-name alias/AWSCookbook107Key