attempt to perform arithmetic (div) on nil. How to fix?

I'm a small game creator i have a problem with Base Health in my TD game how to fix it? problem is: ServerScriptService.Main.Base:20: attempt to perform arithmetic (div) on nil Help pls

local serverstorage = game:GetService("ServerStorage")

local Bindables = serverstorage:WaitForChild("Bindables")

local UpdateHealthEvent = Bindables:WaitForChild("UpdateBaseHealth")

local GameOverEvent = Bindables:WaitForChild("GameOver")

local Base = {}

function Base.Setup(map, health)
	Base.Model = workspace.map.Base
	Base.CurrentHealth = health
	Base.MaxHealth = health
	Base.UpdateHealth()
end

function Base.UpdateHealth(damage)
	if damage then
		Base.CurrentHealth -= damage
	end
	
	local gui = workspace.map.Base.HealthGui
	local precent = Base.CurrentHealth / Base.MaxHealth
	
	gui.CurrentHealth.Size = UDim2.new(precent, 0, 0.5, 0)
	
	if Base.CurrentHealth <= 0  then
		GameOverEvent:Fire()
		print("gameover")
		gui.Title.Text = "Base:Destroyed "
	end
	
	gui.Title.Text = "Base: " .. Base.CurrentHealth .. "/" .. Base.MaxHealth
	
	
end

UpdateHealthEvent.Event:Connect(Base.UpdateHealth())

return Base
~~~~~~~~~~~~~~~~~i

"attempt to perform arithmetic (div) on nil" means you're trying to use the / (division) operator on something that is nil (has no value), and the only sign of division I see is on "Base.CurrentHealth / Base.MaxHealth".

Looking at your code you have a function Base.Setup that assigns values to both Base.CurrentHealth and Base.MaxHealth, but I don't see it mentioned anywhere in the code you specified, possibly the reason why your properties are nil.