Retrieve CPQ users from a group using Rest API

Summary:

Hi, I'm trying to retrieve users from a group via Rest API from a lib function, I'm using superuser basic authentication, however, when this call is performed in the backend with a Sales Agent user, I'm getting an error, please see details below.

Content (please ensure you mask any confidential information):

[ERROR] - {"error_description":"This action requires admin access.","error_uri":"HTTP://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html","error":"This action requires admin access."}

Looking if there is there any restriction about using this approach.

Thank you in advance for any advice.

Version (include the version you are using, if applicable):