My mobile will shut down automatically

well it's really common. I have suffered from this problem for like 3 months. did many hard resets but Everytime it would start crashing after 2-3 weeks. what I found to be there solution is.
1- backup you data manually. don't use SmartSwitch for banking up data. manually copy the folders you need into your computer
2- hard reset
3- restore your data manually.
hope this helps

Hello. My mobile will shut down automatically. My mobile phone is Samsung Galaxy S7 edge.