I have bought 2 of these and both did the same thing,.........after a while they stop working..........the bagel light comes on, so I know it's getting power, but; it refuses to stay down when I put toast in it and push the lever down, it keeps popping back up. If it happened only on the one I'd think I got a bad one, but; on both of them, something sticks! Is there a way I can fix this problem, without having to buy another toaster?