Bus Stops partially missing in zoom level 17

i imported OSM data to PostgreSQL and drawing the map using TileMill. i notice bus_stop show less in zoom level 17 but showing all bus stops in level 18+, do anyone know how to fix this?

/* labels.mss MapCSS*/
#planetosmpoint[amenity='bus_station'][zoom>=10] { point-file: url(res/bus-15.png); }
#planetosmpoint[highway='bus_stop'][zoom>=16] { point-file: url(res/bus-15.png); }