I have a Motorola Moto G (3rd generation) phone w/ Android 6.0.1. Since a day or so I do not get any notifications of missed SMS (text messages) or Whatsapp messages in the status bar at the top of my screen anymore. Missed telephone calls still works. Suffice to say that there's no notification sound either when I receive an SMS or Whatsapp. Haw can I solve this?