Why wont this work?!!!

I'm EXTREMELY frustrated because a double-jump script JUST REFUSES to work in online mode! PLEASE SOMEONE explain why this darn FREAKIN SCRIPT wont work?!!

The error i get is: "Humanoid is not a valid member of model"

WTF... HOWWWWWWWWWWWWWWWWWWWWWW

repeat wait() until script.Parent.Parent.Character and script.Parent.Parent.Character.Humanoid  ~= nil
wait()
print("loaded")
--Made by FromLegoUniverse
--Super easy script
--Put this in StarterGui or StarterPack

--The "Creative" option makes it so you can jump infinitly (True if yes, False if no)
--Note: I modified a decent amount of this. So the update function and "Creative" option do nothing.
local FirstJump = false
local MidJump = false
local Mouse = script.Parent.Parent:GetMouse()
local animation = script.db
debounce = false

function onKeyDown(key)
    Mouse.KeyDown:connect(function(Key)
    if string.byte(Key) == 101 and debounce == false then
        debounce = true
        MidJump = true
    local animPLAY = script.Parent.Parent.Character.Humanoid:LoadAnimation(animation)
    animPLAY:Play()
        script.Parent.Parent.Character.Torso.Velocity = Vector3.new(0,90,0)
        wait(3)
        debounce = false
        end
    end)
end

function Update()
    if script.Parent.Parent.Character.Humanoid.Jump == true then
        FirstJump = true
    else
        FirstJump = false
        MidJump = false
    end
end


--Mouse.KeyDown:connect(onKeyDown)
wait()
script.Parent.Parent.Character.Humanoid.Jumping:connect(onKeyDown)
--script.Parent.Parent.Character.Humanoid.Jumping:connect(Update)