In services/aws.py:list_secret_names() there is no MaxResults nor any pagination code - so in any account with a lot of secrets, it may not return the secret being used - which will then cause create_or_update_secret() to fail creating a new secret instead of updating the existing one.
Alternatively, could refactor the code to call describe_secret instead of list_secrets as this would reduce the IAM policy requirements and also fix pagination issues at the same time.
Thanks, this tool is really helpful :)