CFrame.lerp not working correctly?

So, I'm trying to make one part lerp smoothly to the other part's position, but it's not working correctly. Here's my code.

local RS = game:GetService("RunService")
local p1 = workspace.Part1
local p2 = workspace.Part2
local part = Instance.new("Part", workspace)
part.Anchored = true

wait(6)

RS:BindToRenderStep("LerpToPos", Enum.RenderPriority.Camera.Value, function()
    local alpha = 0
    alpha = alpha + 0.05
    local point = p1.CFrame.lerp(p2.CFrame, 0.2)
    part.CFrame = point
    if alpha == 1 then
        RS:UnbindFromRenderStep("LerpToPos")
    end
end)

It doesn't seem to work correctly, and it always spits out this error: Players.Player.Backpack.LocalScript:12: bad argument #2 to 'lerp' (CFrame expected, got number) Anyone know why? I read on the wiki for the function and I have the argument in the right place, sooo I dunno. Thanks, everyone who reads this.