Object isn't rotating when I'm trying to move it?

I've made a door that moves up and down, but the door itself turns 90 degrees when it starts moving. So I tried to add a way to keep the object at the same rotation as it moves down and up but I'm not doing something right?

door = script.Parent.Door
debounce = false
open = true --Door open or not open


script.Parent.DoorToggle.Event:connect(function() --This is a bindable function which is fired from another script
    if not debounce then
        debounce = true
        if open then
            for i=10,180 do
                door.CFrame = CFrame.new(door.Position + Vector3.new(0,-0.1,0))
                door.Rotation = CFrame.Angles(0,90,0) --Something is wrong here
                wait()
            end
            open = false
        elseif not open then
            for i=10,180 do
                door.CFrame = CFrame.new(door.Position + Vector3.new(0,0.1,0))
                door.Rotation = CFrame.Angles(0,90,0) --Something is wrong here too
                wait()
            end
            open = true
        end
        debounce = false
    end
end)

I've only recently started learning CFraming.