Native Audio cant find my mp3 files

I am using below code to load my mp3 files

this.nativeAudio.preloadSimple(‘sound2’, ‘assets/sound2.mp3’.then(() => {
console.log(‘preload success’)
}, (err) => {
console.log(err);
});

However i get a error when preload the mp3 java.io.FileNotFoundException: www/assets/sound2.mp3
I am sure the sound2.mp3 is placed in both /src/assets/sound2.mp3 and www/assets/sound2.mp3
Anyone got any ideas on it?