How do I resize the HumanoidRootPart? [Solved]

I have created a crawl script to make the character crawl through an opening. I created this localscript parented to StarterCharacterScripts.

local UserInputService = game:GetService("UserInputService")
local Character = script.Parent
local Humanoid = Character:WaitForChild("Humanoid")
local Anim = Humanoid:LoadAnimation(script:WaitForChild("CrawlAnim"))
local AlreadyPlaying = false
Humanoid.Running:Connect(function(Speed)
	if Speed>0 then
		Anim:AdjustSpeed(1)
	elseif Speed==0 then
		Anim:AdjustSpeed(0)
	else
		Anim:AdjustSpeed(-1)
	end
end)


UserInputService.InputBegan:Connect(function(Input)
	if Input.KeyCode == Enum.KeyCode.C then
		if not AlreadyPlaying then
			AlreadyPlaying = true
			Anim:Play()
			Anim:AdjustSpeed(0)
			Humanoid.WalkSpeed = 8
			Humanoid.JumpPower = 0
		else
			Anim:Stop()
			Humanoid.WalkSpeed = 16
			Humanoid.JumpPower = 50
			AlreadyPlaying = false
		end
	end
end)

The problem is that the HumanoidRootPart is blocking the way. Like this. I tried Adding this code to line 5:

coroutine.resume(coroutine.create(function()
	while wait() do
		local HumanoidRootPart = Character:WaitForChild("HumanoidRootPart")
		local UpperTorso = Character:WaitForChild("UpperTorso")
		HumanoidRootPart.Position = UpperTorso.Position
		HumanoidRootPart.Orientation = UpperTorso.Orientation
		HumanoidRootPart.Size = UpperTorso.Size
	end
end))

Then the character starts going like crazy. How do I fix this?