Transition Tower is not generated or sliced

I cannot get the transition tower to generate. I’ve watched the tutorials on dragging colors to the different models and I have tried a variety of methods, even painting parts of my models different colors just to see if the tower would show up. Whenever I slice it’s only ever one color. You can see in the attached image that I have the different models with different colors but no transition tower.

How can I force the transition tower to generate and slice in multiple colors?

I’m using OSX and chrome 87.0.4280.88 if that helps