WatchKit app not shown in dock favorites on Watch

I heard from some customers that my app cannot be added to the dock on their Watch as a favorite, and I confirmed this -- in the Apple Watch app on the phone where we make dock settings, my app does not show up in the list down below where you can normally tap a + to move it into the "favorites" list up above.


The app does show up fine in the dock on the Watch when showing recents, and it has a proper snapshot and behaves as expected.


Was their some project setting or code required in order to be shown as a favorite in the dock? I wouldn't think so, but this has me wondering.