How do I hide a layer outside a particular country or area?

Question

I am showing a map of Azerbaijan using my own map tiles and style. Using mapbox-gl-js v1.12.0

I want to hide the symbols on certain layers (place_city, place_city_large, place_capital) which are NOT in Azerbaijan.

I am not sure the best way to accomplish this.

I have tried

map.setFilter('place_capital', ["==", ["get", "iso_3166_1"], "AZ"]);

But that did not work, I don't know if I have that property (or how to tell).

I was thinking about using the latitude and longitude or a mask applied only to one layer somehow.

Can anyone point me in the right direction?