Why my phone have error ,,android.process.acore was stop working.''? I have a Samsung S3 Neo

[AC Question]

Hi guys!I'm so angry because on my phone (is a Samsung Galaxy S3 Neo) have a error on screen anytime named: ,,The Proces android.process.acore was stop working'' and only reply i can say is ,,OK'' but anytime when i click ,,OK'' ,the error appearly AGAIN AND AGAIN
How to stop this quickly? I need some help. I've had tried some trickies about this,like Clean Contacts Storage data etc BUT DOEN'T WORKED!!!