JJsploit stuck at injecting

When I join a game, I attack JJsploit and It's stuck at ''[Fluxteam->WeAreDevs]: Starting up!'' then after a few minutes it dissapear and It's still not attached. 

Version: 6.4.12 

I did not run it as administrator because the publisher is unknown and I don't know yet if it will damage my pc. I've ran ROBLOX as administrator though. Someone help me with this thing if possible. Thanks!