I am having the same too...at any locations within klang valley.
phone line full bar..but will received sms mentioning i have missed call but my phone never rang at all.
Data plan will stuck there and won't load...
changing from old 3G Micro sim to LTE nano sim...(note 3 to note 5)
but i test my Note 5 with another Nano sim..all working fine..
fed up on it..