Removing a part makes script not work?

I have a tool in starter pack and in that tool I have a part named "Handle" also, a script that has:

r = game:service("RunService")


Tool = script.Parent

local equalizingForce = 236 / 1.2 -- amount of force required to levitate a mass
local gravity = .30 -- things float at > 1

local ghostEffect = nil
local massCon1 = nil
local massCon2 = nil


local head = nil
function recursiveGetLift(node)
	local m = 0
	local c = node:GetChildren()
	if (node:FindFirstChild("Head") ~= nil) then head = node:FindFirstChild("Head") end -- nasty hack to detect when your parts get blown off

	for i=1,#c do
		if c[i].className == "Part" then	
			if (head ~= nil and (c[i].Position - head.Position).magnitude < 10) then -- GROSS
				if c[i].Name == "Handle" then
					m = m + (c[i]:GetMass() * equalizingForce * 1) -- hack that makes hats weightless, so different hats don't change your jump height
				else
					m = m + (c[i]:GetMass() * equalizingForce * gravity)
				end
			end
		end
		m = m + recursiveGetLift(c[i])
	end
	return m
end


function onMassChanged(child, char)
	print("Mass changed:" .. child.Name .. "    " .. char.Name)
	if (ghostEffect ~= nil) then
		ghostEffect.force = Vector3.new(0, recursiveGetLift(char) ,0)
	end
end



function UpdateGhostState(isUnequipping)

	if isUnequipping == true then
		ghostEffect:Remove()
		ghostEffect = nil
		massCon1:disconnect()
		massCon2:disconnect()
	else
		if ghostEffect == nil then
			local char = Tool.Parent
			if char == nil then return end
			ghostEffect = Instance.new("BodyForce")
			ghostEffect.Name = "GravityCoilEffect"
			ghostEffect.force = Vector3.new(0, recursiveGetLift(char) ,0)
			ghostEffect.Parent = char.Head
			ghostChar = char
			massCon1 = char.ChildAdded:connect(function(child)  onMassChanged(child, char) end)
			massCon2 = char.ChildRemoved:connect(function(child)  onMassChanged(child, char) end)
		end
	end
	

end



function onEquipped()
	UpdateGhostState(false)
end

function onUnequipped()
	UpdateGhostState(true)
end


script.Parent.Equipped:connect(onEquipped)
script.Parent.Unequipped:connect(onUnequipped)

When I delete the handle, the script does not work :/

Help needed! Thanks.