I have an issue with using CFrame:lerp And my attempts are not working?

So for my first person shooter I made it so that the fake arms are suppose to move to a specific point when doing a motion which I set but its not working

Here are the variables I set

local moveOffset 		= CFrame.new(0.02, -0.014, -0.009)
local lerpTime 			= .2

The code below is all done in renderstepped (I already did a print to check if moving is true and fakeArms are in the camera which do work as I already set their humanoidrootpart to the camera cframe but its torso is not moving.)

local startCFrame = fakeArms.Torso.CFrame
if moving then
	fakeArms.Torso.CFrame:lerp(startCFrame * moveOffset, lerpTime)
else
	fakeArms.Torso.CFrame:lerp(startCFrame, lerpTime)
end

That did not work so I thought I'd need to keep adding the lerp time so I did it like this next.

local lerpTime 			= 0

Again the code below is all done in renderstepped

local startCFrame = fakeArms.Torso.CFrame
if moving then
	if lerpTime < 1 then
		lerpTime = lerpTime + .2
	end
	fakeArms.Torso.CFrame:lerp(startCFrame * moveOffset, lerpTime)
else
	fakeArms.Torso.CFrame:lerp(startCFrame, lerpTime)
end

If anyone knows the issue thanks for helping me in advance! :) ~KIHeros