How do I fix phone from process system isn't responding?

Hello Nathanael, so sorry to hear about your problem. Considering the details you provided, the only solution i can think of is to do a complete factory reset on the phone. It will delete everything such as pictures, contacts, numbers, applications. But it might fix the problem.

You can do a factory data reset by pressing a combinations of the buttons while the phone is off. Below is a link where you can see how it is done step by step (you can go ahead and skip to 1:20, the first part is how to reset the phone while it is on and working) . Hope this was of some help. Have a good day!

https://www.youtube.com/watch?v=BKafDNpr...