My phone model s7 edge.hangs frequently whenever i open no power saving mode,it will work fine when it is in  full saving mode, i cant use my upi payment apps when it is in full power saving mode.   Can anybody help me.

My hangs suddenly when 1.make a.call2.send whatsapp message3.recieve whatsapp message4.when watching tiktok vedios   It means my smart phone of no use snd it became ordinary  phone.          I tried with two times format.but of no use.

My phone get automatically switched off and restart when I am using app,I tried with safemod  ,same thing happened, van anybody has solution for it.