First method (easyer):
-do what you need to do edit db (add kits, modify player stats, etc), save, exit:
-before launching the game, open moddingway selector, and at the select tournaments you slelect career mode tournaments, posh the button apply tournaments, close moddingway selector, and ready:
-launch the game, start career and so on:
PS:after closing the selector, you do not edit the database again, from my personal exeperience, even opening the db with CM 16 or DB master can create the problem, just start the game directly.
Second method:
Apply wich data base you want from the moddingway selector, make edits at your choice of data base, save, go to where your fifa 16 is installed, make a copy of your db folder inside data, place it elsewhere ( desktop), open moddingway selector, apply again the same data base, copy db folder from your desktop in the game/data folder, overwritte everything, regenerate cand ready.
Needless to say you do not touch again the db also.