Provide read-only viewer access to authenticated users

I have configured ldap with concourse and would like to provide read-only viewer access to any authenticated user. I will be restricting other roles (like member or owner) based on which group the user belongs to.

However, I am not sure how to provide read-only access to authenticated users. I get the following error message:

{“timestamp”:“2019-08-05T17:54:58.428143381Z”,“level”:“error”,“source”:“atc”,“message”:“atc.sky.callback.
failed-to-issue-concourse-token”,“data”:{“error”:“user doesn’t belong to any team”,“session”:“5.4”}}

Please advise on how to do this.

Thanks,
Hemang.