public string ExistChamberAppointmentAvailability(bool availability, int doctorId, int?doctorChamberId)
        {
            int rowAffected = aDoctorGateway.ExistChamberAppointmentAvailability(availability, doctorId, doctorChamberId);

            if (rowAffected > 0)
            {
                return("Success");
            }
            else
            {
                return("Manage Appointment availability changing failed.");
            }
        }