As asked above, are you sure you've installed it correctly? You know the lever on the right goes over top of the screw that holds the needle? Or maybe your W foot has a claw like lever that your needle clamp screw goes in between? Your problem sounds like it is not connected right. Yet you obviously know how to install as you use a W foot on your Singer. I bought a generic (my bad) for my Elna 7100 (quilter) and it would not move either layer of fabric. I totally wasted money on a piece of junk--it just sat there and would not move. So I then bit the bullet and bought the expensive one made for my machine....voila! love it. Hope you get your money back or repair.