I use techno r7. And it giving me issues .please help me .it usually show sysyem ui stopped ...whatsapp stpped .play store stopped ..I don't just like it.I have a lot of message s to reply on whatsapp now .and it not opening .can someone here please help .I have perform reboot mode b4 .it still d same .the worse is that my application I con is also changing to unknon icon.