Error DataTables wont show results Ajax Error and 500 Internal Server Error

Question

I'm new to Laravel PHP Framework and currently continue project that was left by someone. so, because of it, i try to replicate his code to create new data list using DataTables library

what i want to achieve is simple thing, just show data list. it's using new table. I will go advance to create other feature like edit, details, action etc. but currently, just to show the data list is still failed.

Error:

         DataTables warning: table id=table - Ajax error.