Plutonium

The first case, I edit and the changes doesn't apply after joining a server.

I Installed IW5 yesterday and after playing few hours I noticed that after editing my classes and joining a server, all the changes I've made are reverted to default class (names too). I tried editing the classes, restart the game but worked only once. TLDR, I cannot edit classes anymore, I'm stuck with the very first change I did and that's that. Any clue of What's may be the problem? Thanks in advance.