why does code i put in roblox studio doesnt work code example

Example: roblox studio what you something follows you when you mouw

local fire1 = Assets.FireStorm:Clone()
			local cfv1 = Instance.new("CFrameValue", fire1)
			local weld = Instance.new("Weld")
			weld.Part0 = fire1.PrimaryPart
			weld.Part1 = Model.HumanoidRootPart
			weld.Parent = fire1
			cfv1.Value = CFrame.new(math.random(-5,5), math.random(0,5), math.random(1, 5))
			fire1:SetPrimaryPartCFrame(Model.HumanoidRootPart.CFrame * cfv1.Value)
			fire1.Parent = demonfolder
			fire1.Name = "FireStorm1"