Camera extension tubes won't click?

I just purchased a set of Vello extension tubes for my Nikon D3200, and when I attempt to twist them onto the camera body they will not click into place. As a result, the camera tells me there's not a lens attached and I can't take pictures.

Is there a fix to the tubes that I can do myself to make these work?

They should - consult your dealer.

The Vello tubes I found on sale from B&H are supposed to allow full compatibility, and have the same locking-pin arrangement as Nikon's bodies.

I would expect problems from cheap tubes, but not these.

Don't attempt to fix new stuff that doesn't work. If you break either the tubes or the camera you won't get a refund. Take/send them back and get some that do work properly.