Every time `placemarker()` is ran, it creates a new marker. You need to create the marker once outside of the placemarker function and after that, inside placemarker, use `marker.setPosition()`.

Every time `placemarker()` is ran, it creates a new marker.
You need to create the marker once outside of the placemarker function and after that, inside placemarker, use [`marker.setPosition()`](https://developers.google.com/maps/documentation/javascript/reference#Marker).