Google map Info window won't open at first click, instead it will show on second click (ANDROID JAVA)

Question

I am using below code to open up an infowindow in my map:

//Define popup

private View popup=null;

mMap.setInfoWindowAdapter(new GoogleMap.InfoWindowAdapter(){
    @Override
    public View getInfoWindow(Marker marker) {
        return null;
    }
    @Override
    public View getInfoContents(final Marker marker) {
        if(popup == null){
            popup = getLayoutInflater().inflate(R.layout.custom_adress,null);
        }
        final ImageView customadresimage = (ImageView) popup.findViewById(R.id.customadresimage); //my imageview       
        Picasso.get().load(marker.getSnippet()).resize(200,200).into(customadresimage); //save and show photo from firebase  
        return popup;
    }
});

When I clicked pin, photo dont show firstly, when i clicked secondly, photo is shown.

1. First Click
2. Second Click: What is wrong ?