Android BLE , setCharacteristicNotification() doesn't work

Question

I have 6 characteristics on my device. One of them needs notification to send data. I register characteristics like this :

  private void registerEnvironmentCharacteristics(List<BluetoothGattCharacteristic> characteristics) {
        for (BluetoothGattCharacteristic characteristic : characteristics) {
            UUID characteristicUuid = characteristic.getUuid();
            if (Characteristics.TEMPERATURE_CHARACTERISTIC_UUID.equals(characteristicUuid))
                temperatureCharacteristic = characteristic;
            flipNotifications(temperatureCharacteristic,true);
        }
    }

This is my flip method to setCharacteristicNotification :

 private void flipNotifications(BluetoothGattCharacteristic characteristic, boolean enable) {
        boolean notifications = bluetoothGatt.setCharacteristicNotification(characteristic, enable);
        BluetoothGattDescriptor descriptor = characteristic.getDescriptor(Characteristics.CONFIGURATION_DESCRIPTOR_UUID);
        descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
        bluetoothGatt.writeDescriptor(descriptor);
        BluetoothCommunicationManager.getInstance().add(new DescriptorCommand(descriptor, bluetoothGatt, enable ? BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE : BluetoothGattDescriptor.DISABLE_NOTIFICATION_VALUE));

    }

When I delete flipNotification() method from registerEnvironment I've go 5 characteristics from device (without this one with notification) but when I add flipNotification I'm getting null on all characteristics. Any idea what am I doing wrong ? This is my wrtiting method :

 public void readTemperature() {
        BluetoothCommunicationManager.getInstance().add(new WriteCharacteristicCommand(temperatureCharacteristic, bluetoothGatt, SINGLE_READ_COMMAND));
    }

Thanks in advance for every help!