Elevator goes haywire, why?

So, my block of code looks like this:

local ElevatorParts = script.Parent.Parent:GetChildren()
script.Parent.ClickDetector.MouseClick:connect(function()
    if script.Parent.Parent.FloorNumber.Value < 2 then
        if script.Parent.Parent.InUse.Value == false then
            script.Parent.Parent.InUse.Value = true
            for _,v in pairs(script.Parent.Parent:GetChildren()) do
                if v.ClassName == "Part" then
                    v.CFrame = v.CFrame * CFrame.new(v.Position.X, v.Position.Y + 1, v.Position.Z)
                end
            end
        end
    end
end)

The expected output is the elevator's parts moving up one unit on the y axis, but instead turns into a black hole.