API management - User search: Field

I am trying to filter the request using filed as per described: A comma separated list of fields to include or exclude (depending on include_fields) from the result, empty to retrieve all fields.

I am getting the following message:

{
  "statusCode": 400,
  "error": "Bad Request",
  "message": "Query validation error: 'String does not match pattern ^(([a-zA-Z0-9_\\\\.]+))(,(([a-zA-Z0-9_\\\\.]+)))*$: email, user_metadata.name' on property fields (A comma separated list of fields to include or exclude (depending on include_fields) from the result, empty to retrieve all fields).",
  "errorCode": "invalid_query_string"
}

You have a space character in the value you’re providing for the fields option. If you use email,user_metadata.name instead of email, user_metadata.name (space after comma) then the request should complete successfully or at least it should not complain about that error.