When a cloud is not found in your credentials file, the credentials are not listed. In addition, the credentials error given is confusing, and non-consistent.
nskaggs@pixel:~$ juju list-credentials
ERROR removing secrets from credentials for cloud maas18: cloud maas18 not found
nskaggs@pixel:~$ juju list-credentials
ERROR removing secrets from credentials for cloud munna-vmaas: cloud munna-vmaas not found
nskaggs@pixel:~$ juju list-credentials
ERROR removing secrets from credentials for cloud silcoon-vmaas: cloud silcoon-vmaas not found
nskaggs@pixel:~$ juju list-credentials
ERROR removing secrets from credentials for cloud jujuqa-stack: cloud jujuqa-stack not found
nskaggs@pixel:~$ juju list-credentials
ERROR removing secrets from credentials for cloud maas19: cloud maas19 not found
nskaggs@pixel:~$ juju list-credentials
ERROR removing secrets from credentials for cloud silcoon-vmaas: cloud silcoon-vmaas not found
nskaggs@pixel:~$ juju list-credentials
ERROR removing secrets from credentials for cloud silcoon-vmaas: cloud silcoon-vmaas not found
Juju should still list all credentials in the file, as well as displaying a friendly warning about any clouds it cannot find.
Status changed to 'Confirmed' because the bug affects multiple users.