Why is my galaxy s7

[AC Question]

So i bought an s7 2 days ago. From day 1, it started to give me video error ( instagram, facebook,youtube). I fixed the problem by restarting the phone. Sometimes my phone is not ringing or i dont hear notification sound ( and its not on silent). I fixed this problem too by restarting phone. Day 2...both problems reapear. How can i fix this?