Keyboard bindings problem on Mac Yosemite

Hi everybody. Playing on mac Yosemite and having a really frustrating issue with character not being able to move forward (W key doesnt respond), i’ve been able to play normally for one day, then it bugged.
I can move if i change the key, but is just terrible.
Been looking other threads and found only about windows, with similar problems (talks about programs like synergy, but never heard about it).
Tried to restart game, computer, but it just keeps tripping.
Would updating to El capitan (latest mac software) change anything?
Is there a way to reset this situation? Thanks in advice

kinda solved the issue, the problem is that game switched keyboard keys, w now stands for z.
can play now, but still would like to know why the game trips like this without a reason