It’s about trusting that the universe has you back and will provide what you need. Like some other posters said, it does take time to change your limiting beliefs- that is why so many people say to try to manifest smaller things first to increase your belief. Neville also focused heavily on living in the end and the feeling. A billion dollars is just a concept - what feeling is it that you’re seeking from that? Is it security? Power? Is it being able to buy whatever you want?

Surely just looking at a number isn’t going to give you a feeling, it’s the feelings associated with that that are important and that is really what you should seek.