Why doesn't the text changing work?

I made a gui for my weapons to show their ammo & stuff, the ammo shows up, shows the right amount of ammo, but when I fire with my gun my currentammo doesn't change ;/

local players = game:GetService("Players")
local player = players.LocalPlayer
local weapon = .Parent
local ammo = .Parent:WaitForChild('CurrentAmmo')
local maxammo = .Parent:WaitForChild('MaxAmmo')

weapon.Equipped:connect(function()
	local gui = Instance.new('ScreenGui', player.PlayerGui)
	gui.Name = 'WeaponGui'
	local currentammogui = Instance.new('TextLabel', gui)
	currentammogui.Name = 'CurrentAmmo'
	currentammogui.Text = 'Current: '..ammo.Value
	currentammogui.Size = UDim2.new(0.17, 0, 0.07, 0)
	currentammogui.Position = UDim2.new(0.81, 0, 0.9, 0)
	currentammogui.BackgroundTransparency = 1
	currentammogui.FontSize = 'Size28'
	currentammogui.Font = 'Code'
	local maxammogui = Instance.new('TextLabel', gui)
	maxammogui.Name = 'MaxAmmo'
	maxammogui.Text = 'Max: '..maxammo.Value
	maxammogui.Size = UDim2.new(0.17, 0, 0.07, 0)
	maxammogui.Position = UDim2.new(0.81, 0, 0.85, 0)
	maxammogui.BackgroundTransparency = 1
	maxammogui.FontSize = 'Size28'
	maxammogui.Font = 'Code'
end)

ammo.Changed:connect(function(newammo)
	local currentammogui = player.PlayerGui.WeaponGui:WaitForChild('CurrentAmmo')
	currentammogui.Text = 'Current: '..newammo
end)

weapon.Unequipped:connect(function()
	player.PlayerGui.WeaponGui:Remove()
end)

Help me ;p

Use a while loop on the

currentammogui.Text = 'Current: '..ammo.Value

Like this

while wait(10) do
--script to change value
end

EDIT: READ ME

The function is asking to create a GUI inside the game.Players. There is no PlayerGui in the game.Players. There is one on each game.Player.LocalPlayer.

local gui = Instance.new('ScreenGui', player.LocalPlayer.PlayerGui)
gui.Name = 'WeaponGui'