How to disable and enable back a script?

Hi i created a part that when u click it disable a script that contains the ”MainScript”, and it works, but.. it just that when i enable the script, the script woldnt work, do u guys know why? :D i use this script to”close it”:

       MainGame = game.ServerScriptService.MainGame
function onClick(click)
    wait(0.5)
MainGame.Disabled = true

end

script.Parent.ClickDetector.MouseClick:connect(onClick)

and to ”open it” :

MainGame = game.ServerScriptService.MainGame
 function onTouch(hit)
wait(0.5)
MainGame.Disabled = false

end

script.Parent.Touched:connect(onTouch)

but,as i sayd, when you ”open it” it woldnt work...