Why is the view port frame not displaying anything?[SOLVED]

Basically I have two buttons that if you click a gun preview will appear on the viewport. Except it does not display the gun. I have the camera and everything set up and working. I got no errors and I checked to make sure it was going in the viewport and It was.

Here is my code

--August 1 2020
--Test script for the viewport frame
--
--Made by: Mikey2019d

---------------
-- Constants --
---------------
local cam = game.Workspace.CurrentCamera
local Guns = game.Workspace.Weapons
local ViewPort = game.Players.LocalPlayer.PlayerGui.ScreenGui.ViewportFrame
local Buttons = game.Players.LocalPlayer.PlayerGui.ScreenGui.GunLables
local ChildrenOfViewport = ViewPort:GetChildren()
---------------------
-- Set Camera type --
---------------------
cam.CameraType = "Scriptable"

-----------------
-- Main script --
-----------------
for i,button in pairs(Buttons:GetChildren()) do
	button.MouseButton1Click:Connect(function()
		local gunSelected = button.Name
		for i,Gun in pairs(Guns:GetChildren()) do
			if Gun.Name == gunSelected then
				local focus = Gun:FindFirstChild(tostring(Gun.Name) .. "FOC").CFrame
				cam.CFrame = focus
				local gunClone = Gun:Clone()
				gunClone.Parent = ViewPort				
			end
		end
	end)
end

Thanks for reading and hopefully answering my question. Sorry if it is an obvious mistake.

EDIT: Silly me I forgot to set the viewport camera. So for anyone who is having the same issue here is what you have to do.

----------------------------
-- Viewport camera --
----------------------------

Viewport.CurrentCamera = The camera you selected

Hope this answer made sense and helped.