Help i got hacked

wtf so i had like 10 people on my server when this guy Tquaidznz joined and then he told me how he could execute serverside lua on my server and then he made everyone Superadmin,Wtf is this, how is that possible.

his steam id:

next time don’t use leaks

“Help I got hacked” -_- Your server got hacked, Get Cake Anti Cheat ay.

next time dont type in youtube “free gmod hacks get admin instantly 2015”

Start by deleting your leaks.
Next, go to scriptfodder and buy the scripts.
People work really hard on these scripts and they deserve the proper respect.