One of these is not working. When I pull the handle to raise it does, but the return spring to raise the handle doesn't work, so next time I press the lift, nothing happens. I have to use a screwdriver to open the spring system. Once I do that I can pull the handle and it will go up. The object I'm lifting is only 70 pounds and I have one on each side so 30-40 pounds max per lift. The other seems to work fine. Very annoying.