Scenes already have a built-in emitter, in events, so you don’t have to create your own. (You still can if you want, though.)
Make sure you’re emitting from and listening to the same emitter. It should be something like
// In Level_OneScene:
this.events.emit('upPoints' /*…*/);
// In HUDScene:
this.scene.get('Level_One').events.on('upPoints' /*…*/);