Knockback wont work

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1

i have a punch script that should inflict knockback on the thing when it hits it. Though it wont work and I get this error:

Workspace.trueblockhead101.Punch.LocalScript:48: attempt to index nil with ‘CFrame’

local tool = script.Parent
local player = game.Players.LocalPlayer
local character = player.Character or player.CharacterAdded:Wait()
local humanoid = character:WaitForChild("Humanoid")



local InputService = game:GetService("UserInputService")
local InputType = Enum.UserInputType

local animation = nil
local slashAnimation = nil

tool.Equipped:Connect(function()
	animation = Instance.new("Animation")
	animation.AnimationId = "rbxassetid://7118111810"
	slashAnimation = humanoid:LoadAnimation(animation)
end)

tool.Unequipped:Connect(function()
	animation:Destroy()
	slashAnimation = nil
end)

local debounce = false
InputService.InputBegan:Connect(function(input, processed)
	if input.UserInputType == InputType.MouseButton1 and slashAnimation and not processed then
		if debounce == false then
			debounce = true

			slashAnimation:Play()
			local Connection
			local tool = script.Parent

			local function onTouch(partOther)

				local humanOther = partOther.Parent:FindFirstChild("Humanoid")

				if not humanOther then return end

				if humanOther.Parent == tool then return end

				humanOther:TakeDamage(5)
				local KnockBack = Instance.new("BodyVelocity")
				KnockBack.P = math.huge
				KnockBack.Parent = humanOther:FindFirstChild("HumanoidRootPart")
				KnockBack.MaxForce = Vector3.new(math.huge,math.huge,math.huge)
				KnockBack.Velocity = humanOther:FindFirstChild("HumanoidRootPart").CFrame.lookVector * -70
				game.Debris:AddItem(KnockBack, 0.3)
				if humanOther.Health <= 0 then
					player.leaderstats.Souls.Value =  player.leaderstats.Souls.Value + 1 
					humanOther.Parent:Destroy()
				end
			end

			Connection = tool.Handle.Touched:Connect(onTouch)

			slashAnimation.Stopped:Wait() 
			debounce = false
			Connection:Disconnect()
			wait(.2)
			debounce = false

		end

	end
end)

Im honestly sure if i wrote the knock back script correctly, but im stumped.