Drone-mvn-auth issue using secrets

using the drone docker runner, running in k8s
And trying to use the drone-mvn-auth to create settings.xml for java builds.
Docs indicate you can use a secret (created in drone UI) for some of the parts, like servers.
Downloaded the code from github and it works fine with this input for servers as an example:
[{“id”: 123, “username”: “bobo”, “password”: “ziphead”},{“id”: 234, “username”: “cbobo”, “password”: “zziphead”}]
But, can’t get it to work using an actual secret defined at organization level inside.
Defining the secret as ‘maven_servers’ with the string above.
And then in the pipeline as:

  • name: authenticate
    image: robertstettner/drone-mvn-auth
    pull: true
    secrets: [ MAVEN_SERVERS ]
    - id: my-profile

    can’t find any help anywhere…ideas?