I have a K8 cluster on GCP running elasticsearch. Now I need to create a backup.

I've installed the GCS-plugin on my pods in stateful-set and tried setting it up with the following documentation: https://github.com/elastic/elasticsearch/blob/master/docs/plugins/repository-gcs.asciidoc

When I try to configure a repository to use credentials stored in keystore I get the following response back:

{
    "error": {
        "root_cause": [
            {
                "type": "repository_exception",
                "reason": "[my_backup] repository type [gcs] does not exist"
            }
        ],
        "type": "repository_exception",
        "reason": "[my_backup] repository type [gcs] does not exist"
    },
    "status": 500
}

Any lead would be helpful, thanks!