Hi, the 3PDT switches are pretty sturdy and difficult to break, but once in a while you can get a defective one.
The best way to confirm that it is broken is to use a multimeter (I am not sure if you have one), You can check continuity between the pins and they should be linked like this:
The middle pins are connected to the top or to the bottom pins "depending on the click"
Please let me know about your progress