I am new to Javascript and mapbox and I want some help to solve an issue (code below). I am using some coordinates ({{coords}}) coming from a python script and I am adding them as a geojson to the map (featureCollection). I want these geojson coordinates to be updated every 2 seconds. I have used setData(), but my coordinates are not refreshing on the map. Can you help and give some hints? Thank you very much.

var longLat = {{coords}};
var featureCollection = [];

for(var itemIndex in longLat) {
featureCollection.push({
    "type": "Feature",
    "geometry": {
      "type": "Point",
      "coordinates": longLat[itemIndex]
    },
    "properties": {
      "title": "boat",
      "icon": "ferry"
    }
  });
}
map.on('load', function () {

map.addSource('ship', { type: 'geojson', data: featureCollection });
  map.addLayer({
    "id": "points",
    "type": "symbol",
    "source": {
    "type": "geojson",
      "data": {
        "type": "FeatureCollection",
        "features": featureCollection
      }
    },
    "layout": {
      "icon-image": "{icon}-15",
      "text-field": "{title}",
      "text-font": ["Open Sans Semibold", "Arial Unicode MS Bold"],
      "text-offset": [0, 0.6],
      "text-anchor": "top"
    }
  });

window.setInterval(function() {

  map.getSource('ship').setData(featureCollection);
}, 2000);

});