string delURL = $"{settings.RestUrl.value}{settings.RestVersion.value}/directoryRoles/{settings.GuestInviterRoleObjectID.value}/members/{user.id}/$ref";

                    HttpResponseMessage payload = await client.DeleteAsync(delURL);

                    Task<string> json = payload.Content.ReadAsStringAsync();

                    JObject o = new JObject();

                    if (json.Result.Length > 0)
                    {
                        o = JObject.Parse(json.Result);
                    }

error:  code:"authorization_requestDenied",
messsage: "Insufficient privileges to complete the operation"  ....