My code is supposed to clone characters, but instead errors! Help?

So I'm trying to make a zombie script where anyone that dies gets infected. In order to do this, I need to clone the player but I get this error message saying;

16:38:33.643 - Workspace.Arcerion.zombify:5: attempt to index local 'zombie' (a nil value)

So the issue with this, I assume is because Roblox doesn't allow cloning a player's character, but I've seen people do it before. Now I could always create a npc that transforms into the character, but I know that there's another way to do this.

Here is the code I've sent, it's really simple because let's be honest when I script and run into an issue I want to solve it before continuing. I just can't resolve this issue, so I'm asking for help.

Code;

local character = script.Parent

local zombie = character:clone()

zombie.Parent = workspace

local rooty = character:FindFirstChild("HumanoidRootPart")


if rooty ~= nil then

	zombie:MoveTo(rooty.Position)

end