Got hacked. [GM please assist]

Ok, I was playing and I get the notice that I was logged in on other computer.
So immediately, i went to z8 and tried to signed in, i realised my account was hacked by someone. I retrieved it back my email.
As I went back to the game, I was shocked that the hacker bought useless stuffs like GSG9, STAR, got a Mp5 Adv, Micro Galil scope, field shovel, extra GP crates that I didn't had, AWM R Dragon crates and many more backgrounds.

What should I do now?